| # |
| 10-K | Annual Report (Form 10-K) | Annual SEC report. Most comprehensive mandatory filing. | — | format |
| 10-Q | Quarterly Report (Form 10-Q) | Quarterly SEC filing. Unaudited. | — | format |
| 10b5-1 | Rule 10b5-1 Trading Plan | Pre-planned insider sale schedule. Weaker signal than discretionary sales. | — | format |
| 8-K | Current Report (Form 8-K) | Ad-hoc filing for material events (earnings, M&A, CEO change). | — | format |
| A |
| AD | Airworthiness Directive | Mandatory FAA (or equivalent) regulatory order requiring aircraft operators to perform specific inspections, repairs, or modifications. Can affect engine OEM cost recovery and Services margins. | — | format |
| adj op margin | Adjusted Operating Margin | Operating income (excluding stock-based compensation + one-time items) divided by revenue. Non-GAAP. Most software companies report both GAAP and adjusted versions; the gap is mostly SBC. | <10% subscale · 10-25% maturing · 25-40% strong · >40% best-in-class | profitability |
| ADR | Average Daily Range | Average daily price range over N days, in percent. | — | technical |
| ARR | Annual Recurring Revenue | Annual recurring revenue (typical SaaS metric). | — | industry |
| ASIC | Application-Specific Integrated Circuit | A chip custom-designed for one workload (e.g. an AI accelerator or switch) rather than a general-purpose CPU/GPU. Higher performance-per-watt for its target task; high upfront design (NRE) cost. | — | memory |
| ASP | Average Selling Price | Average selling price per unit (memory: per GB). | — | memory |
| ATH | All-Time High | Highest price ever reached. | — | technical |
| ATL | All-Time Low | Lowest price ever reached. | — | technical |
| ATM | At-the-Money | Option with strike ≈ current price. | — | technical |
| ATR | Average True Range | Average daily range. Useful for stop-loss placement. | — | technical |
| B |
| B2B | Business-to-Business | Sales to other businesses. | — | industry |
| B2C | Business-to-Consumer | Sales to end consumers. | — | industry |
| BB | Bollinger Bands | Volatility band: moving average ± 2 standard deviations. | — | technical |
| Bear Steelman | Bear Steelman | Discipline of formulating the strongest possible counter-argument to your own thesis. | — | skill |
| Beta | Beta | Volatility relative to market. 1 = market-like, >1 more volatile, <1 less volatile. | <0.8 defensive · 0.8-1.2 market-like · 1.2-1.8 cyclical · >1.8 highly volatile | technical |
| Bit Growth | Bit Growth | Growth of memory bits shipped — primary demand metric. | — | memory |
| BoD | Board of Directors | Board of directors. | — | industry |
| Bp | Basis Point | 1 bp = 0.01 percentage point. 100 bps = 1%. | — | macro |
| Bps | Basis Points | Plural of bp. | — | macro |
| BU | Business Unit | Business segment within a corporation. | — | industry |
| C |
| CAC | Customer Acquisition Cost | Cost to acquire a new customer. | — | industry |
| CAGR | Compound Annual Growth Rate | Geometric average growth rate per year over multiple periods. | — | growth |
| Calendar Year | Calendar Year | The Jan-Dec calendar period. Used to distinguish from Fiscal Year (FY) when comparing companies with non-calendar fiscal years. | — | growth |
| CANSLIM | CANSLIM (O'Neill Framework) | Growth-stock screening: Current EPS, Annual EPS, New, Supply/Demand, Leader, Institutional, Market direction. | — | skill |
| CapEx | Capital Expenditures | Investments in physical assets (factories, machinery, infrastructure). | — | profitability |
| Capital Cycle | Capital Cycle (Marathon) | Sector-investing framework: returns fluctuate with industry CapEx cycles (entrant pressure vs discipline). | — | skill |
| CEO | Chief Executive Officer | Chief executive. | — | industry |
| CFO | Chief Financial Officer | Chief financial officer. | — | industry |
| Churn | Churn Rate | Customer attrition rate per period. | <5% very good · 5-10% ok · >15% problematic | industry |
| COGS | Cost of Goods Sold | Direct production costs of goods sold. | — | profitability |
| COO | Chief Operating Officer | Chief operating officer. | — | industry |
| Core CPI | Core Consumer Price Index | CPI excluding food and energy. | — | macro |
| Core PCE | Core Personal Consumption Expenditures | PCE excluding food and energy. Fed's main benchmark. | — | macro |
| CPI | Consumer Price Index | Consumer price index — primary inflation measure. | <2% low · 2-3% near Fed target · 3-5% elevated · >5% crisis | macro |
| CPU | Central Processing Unit | General-purpose processor — the main compute core of a server or PC (x86: Intel/AMD; Arm). | — | memory |
| CTO | Chief Technology Officer | Chief technology officer. | — | industry |
| Current Ratio | Current Ratio | Current assets / current liabilities. Short-term liquidity. | <1 problematic · 1-1.5 ok · 1.5-3 solid · >3 possibly inefficient | liquidity |
| Curve Inversion | Yield Curve Inversion | Short-term yields above long-term (e.g., 10y < 2y). Historical recession indicator. | — | macro |
| CXMT | ChangXin Memory Technologies | China's largest DRAM manufacturer. Emerging competitor to Samsung/SK Hynix/Micron. | — | memory |
| D |
| D/E | Debt / Equity | Debt relative to equity. Capital-structure indicator. | <0.3 conservative · 0.3-1.0 normal · >1.5 aggressive | leverage |
| DAU | Daily Active Users | Daily active users (social/app metric). | — | industry |
| DCF | Discounted Cash Flow | Valuation method: future free cash flows discounted to present value. | — | valuation |
| DEF 14A | Definitive Proxy Statement | Annual proxy filing — contains executive compensation, director bios, shareholder proposals. | — | format |
| DFEDTARU | Fed Funds Target Range (Upper) | Upper bound of the Fed Funds target corridor. | — | macro |
| DFF | Federal Funds Rate (Effective) | Effective US policy rate (weighted market average). | — | macro |
| DGS10 | 10-Year Treasury Constant Maturity | FRED series code for the 10-year UST yield. | — | macro |
| DGS2 | 2-Year Treasury Constant Maturity | FRED series code for the 2-year UST yield. | — | macro |
| Div Yield | Dividend Yield | Annual dividend per share divided by the current share price. | — | valuation |
| Dividend Yield | Dividend Yield | Annual dividend per share divided by the current share price. | — | valuation |
| DRAM | Dynamic Random Access Memory | Main memory (RAM). Largest memory market by revenue. | — | memory |
| Drawdown | Drawdown | Maximum percent loss from peak to trough over a period. | — | technical |
| DXY | US Dollar Index | USD exchange rate vs basket of 6 major currencies. | — | macro |
| E |
| EAR | Export Administration Regulations | US export controls administered by the Department of Commerce, covering dual-use commercial and defense technologies. | — | format |
| EBIT | Earnings Before Interest and Taxes | Operating profit before interest and taxes. Core measure of operating profitability. | — | profitability |
| EBITDA | Earnings Before Interest, Taxes, Depreciation, Amortization | Operating cash earnings before all non-cash items. Popular for LBO/PE analysis. | — | profitability |
| EDGAR | Electronic Data Gathering, Analysis, Retrieval | SEC database of all public-company filings. | — | format |
| EMA | Exponential Moving Average | Exponentially weighted average — recent prices weighted more heavily. | — | technical |
| EPS | Earnings Per Share | Profit per share. Net income / diluted share count. | — | profitability |
| ESG | Environmental, Social, Governance | Sustainability rating criteria. | — | industry |
| EV | Enterprise Value | Market cap + net debt + minorities. What you'd pay to acquire the whole firm. | — | valuation |
| EV/EBITDA | Enterprise Value / EBITDA | Values EV against operating cash EBITDA, ignoring capital structure. | <6 very cheap · 6-10 fair · 10-15 growth · >15 expensive | valuation |
| EV/Sales | Enterprise Value / Sales | EV relative to revenue — comparable to P/S but capital-structure adjusted. | — | valuation |
| EVP | Executive Vice President | Senior VP rank (just below C-suite). | — | industry |
| F |
| Fab | Fabrication Plant | Semiconductor factory (wafer production). | — | memory |
| FCF | Free Cash Flow | Operating cash flow minus CapEx. Cash freely available for dividends, buybacks, M&A. | Negative bad (except growth phase) · growing good · stable/high ideal | profitability |
| FCF Margin | Free Cash Flow Margin | FCF / Revenue. How much cash per dollar of sales? | <5% thin · 5-15% solid · 15-25% strong · >25% premium | profitability |
| FCFE | Free Cash Flow to Equity | FCF after debt service — the portion belonging to equity holders. | — | valuation |
| FCFF | Free Cash Flow to Firm | FCF before capital structure — belongs to equity + debt holders. | — | valuation |
| Federal Reserve | Federal Reserve | US central bank. | — | macro |
| Float | Public Float | Freely tradeable share count (excluding insider/restricted holdings). | — | format |
| FOMC | Federal Open Market Committee | Monetary policy committee of the Fed (8 meetings/year). | — | macro |
| Form 4 | Statement of Changes in Beneficial Ownership | Insider transactions (purchases/sales by officers/directors). | — | format |
| Forward (Fwd) | Forward / Forward-Looking | A metric projected for a future period, typically next twelve months (NTM) or next fiscal year. Example: Forward P/E = price divided by EPS expected for next FY. Distinguished from TTM (trailing twelve months) which is backward-looking. | — | growth |
| Foundry | Semiconductor Foundry | Contract manufacturer (TSMC, Samsung Foundry, GlobalFoundries). | — | memory |
| FRED | Federal Reserve Economic Data | St. Louis Fed database of thousands of economic time series. | — | macro |
| FY | Fiscal Year | A company's accounting year, often different from the calendar year. Examples: Apple FY ends late September, Micron in late August, Walmart in late January, IBM and most others in late December. Always specify which FY when comparing peers with different year-ends. | — | growth |
| FY-Q1 | Fiscal Year, Quarter 1 | The first quarter of a company's fiscal year. Note this may NOT correspond to calendar Q1 (Jan-Mar). Apple FY-Q1 = Oct-Dec, Micron FY-Q1 = Sep-Nov, IBM FY-Q1 = Jan-Mar. | — | growth |
| FY26e | Fiscal Year 2026 Estimate | Estimated/forecast results for the company's fiscal year 2026. The 'e' suffix means estimated - usually consensus analyst estimate or management guidance. Forward-looking; not actual reported financials. Always tagged (est) per language-calibration discipline. | — | growth |
| G |
| GAAP | Generally Accepted Accounting Principles | US accounting standards (official, SEC-compliant). | — | profitability |
| GARP | Growth at a Reasonable Price | Lynch style: growth stocks at reasonable valuation (PEG-oriented). | — | skill |
| GDP | Gross Domestic Product | Gross domestic product. | — | macro |
| GM | Gross Margin | (Revenue − COGS) / Revenue. How much remains after direct product costs? | <20% commodity · 20-40% industry · 40-60% brand/software · >60% very strong | profitability |
| GPU | Graphics Processing Unit | Massively parallel processor originally for graphics, now the dominant general-purpose AI training/inference chip (NVIDIA, AMD). | — | memory |
| H |
| HBM | High Bandwidth Memory | 3D-stacked DRAM for AI accelerators (GPUs). High-margin vs commodity DRAM. | — | memory |
| HBM3E | HBM3 Extended | 5th HBM generation, primarily shipping in NVIDIA H200/B200 in 2024-25. | — | memory |
| HBM4 | HBM4 (Generation 4) | 6th HBM generation, ramping in 2026. 16-Hi variant in development for 2H26. | — | memory |
| Hyperscaler | Hyperscaler | Major cloud provider (AWS, Azure, GCP, Meta, Oracle). | — | industry |
| I |
| ICR | Interest Coverage Ratio | EBIT / interest expense. How many times does earnings cover interest? | <2 risky · 2-5 ok · 5-10 solid · >10 very safe | leverage |
| Insider | Insider (Corporate) | Officer, director, or >10% holder — must report via Form 4. | — | format |
| IPO | Initial Public Offering | Initial public offering. | — | industry |
| IR | Investor Relations | Investor-relations function. | — | industry |
| ITAR | International Traffic in Arms Regulations | US export controls administered by the State Department, covering defense articles and services. | — | format |
| ITM | In-the-Money | Option with intrinsic value (call: strike < price; put: strike > price). | — | technical |
| IV | Implied Volatility | Expected volatility implied by option prices. | — | technical |
| J |
| JV | Joint Venture | A legal partnership in which two or more firms share ownership, risk, and profit of a specific business. CFM International (GE + Safran 50/50) is a leading aerospace JV example. | — | industry |
| L |
| LBO | Leveraged Buyout | Acquisition financed heavily with debt. | — | industry |
| LTA | Long-Term Agreement | Multi-year supply contract with fixed-pricing structure. Smooths memory cycles. | — | memory |
| LTM | Last Twelve Months | Synonym for TTM. | — | growth |
| LTV | Customer Lifetime Value | Expected revenue contribution from a customer over their lifetime. | — | industry |
| M |
| M&A | Mergers & Acquisitions | Mergers and acquisitions. | — | industry |
| MA200 | 200-Day Moving Average | Average of the last 200 closing prices. Long-term trend line — above/below = bull/bear regime. | — | technical |
| MA50 | 50-Day Moving Average | Average of the last 50 closing prices. Medium-term trend line. | — | technical |
| MACD | Moving Average Convergence Divergence | Difference between two EMAs (typically 12 and 26), with a signal line (EMA 9). Trend + momentum. | — | technical |
| Margin of Safety | Margin of Safety | Graham principle: purchase price significantly below intrinsic value as buffer. | — | skill |
| MAU | Monthly Active Users | Monthly active users. | — | industry |
| MD&A | Management's Discussion & Analysis | Narrative section of 10-K/10-Q — management's explanation of results. | — | format |
| Mkt Cap | Market Capitalization | Share price × shares outstanding. Total equity value at market. | — | valuation |
| Moat | Economic Moat | Buffett term: durable competitive advantage (brand, cost, network, switching costs). | — | skill |
| MOVE | MOVE Index | Expected volatility of US Treasuries — bond-market analog to VIX. | — | macro |
| MRO | Maintenance, Repair, and Overhaul | Aftermarket services performed on commercial and defense aircraft, engines, and components. A key recurring-revenue stream for aerospace OEMs and independent shops. | — | industry |
| MRR | Monthly Recurring Revenue | Monthly recurring revenue. | — | industry |
| N |
| NAND | NAND Flash Memory | Non-volatile memory (SSDs, smartphones). | — | memory |
| ND | Net Debt | Total debt minus cash and equivalents. | — | leverage |
| ND/EBITDA | Net Debt / EBITDA | Leverage measured against operating cash flow. How many years of EBITDA to pay off debt? | <1 very conservative · 1-3 normal · 3-5 high · >5 risky | leverage |
| NIC | Network Interface Card | Adapter connecting a server to the network. In AI data centers, high-speed (400G/800G) NICs are critical for cluster scale-out. | — | memory |
| NM | Net Margin | Net income / Revenue. End profitability after taxes and interest. | <3% thin · 3-10% normal · 10-20% strong · >20% premium | profitability |
| Non-GAAP | Non-GAAP / Adjusted Earnings | Management-adjusted numbers (often excluding SBC, restructuring, M&A costs). Caution: often flattering. | — | profitability |
| NOPAT | Net Operating Profit After Tax | EBIT × (1 − tax rate). Operating profit after taxes but before financing. | — | profitability |
| NRR | Net Revenue Retention | Revenue change from existing customers (upsell − churn). | <100% shrinking · 100-110% solid · >120% strong | industry |
| O |
| OCF | Operating Cash Flow | Cash flow from ongoing business operations (before investments). | — | profitability |
| ODM | Original Design Manufacturer | Contract manufacturer that both designs and builds a product, which a brand then sells under its own name. Common in servers, networking gear, and consumer electronics. | — | industry |
| OE | Original Equipment | The sale of new equipment (e.g., a new jet engine sold to an aircraft manufacturer). Contrasts with 'Services' or 'Aftermarket' revenue, which comes from parts, repairs, and maintenance on already-delivered equipment. | — | industry |
| OEM | Original Equipment Manufacturer | Manufacturer that integrates other firms' components into end products. | — | industry |
| OHLC | Open, High, Low, Close | The four core data points of a candle: open, high, low, close. | — | technical |
| OM | Operating Margin | Operating income (EBIT) / Revenue. Profitability after operating costs. | <5% weak · 5-15% solid · 15-25% strong · >25% premium | profitability |
| OTM | Out-of-the-Money | Option without intrinsic value (opposite of ITM). | — | technical |
| P |
| P/B | Price / Book Ratio | Market cap divided by book value of equity. How is the valuation relative to balance-sheet substance? | <1 below book · 1-2 cheap · 2-4 fair · 4-8 growth-oriented · >8 very expensive | valuation |
| P/E | Price / Earnings Ratio | Share price divided by earnings per share. How many years of earnings does the stock cost? | <10 very cheap · 10-15 cheap · 15-25 fair · 25-40 expensive · >40 very expensive (context: growth, cyclicality) | valuation |
| P/S | Price / Sales Ratio | Market cap divided by revenue. Useful for non-profitable growth companies. | <1 very cheap · 1-3 fair · 3-8 growth · >10 highly valued | valuation |
| P/TBV | Price / Tangible Book Value | Like P/B, but after deducting goodwill and intangibles. Stricter asset measure. | <1 below tangible book · 1-2 fair · >3 expensive | valuation |
| PCE | Personal Consumption Expenditures | Fed's preferred inflation measure (vs CPI). | Fed target: 2% core PCE | macro |
| PEG | Price / Earnings to Growth | P/E divided by expected earnings growth rate. Lynch's favorite metric. | <0.5 unusually cheap · 0.5-1 cheap · 1-2 fair · >2 expensive | valuation |
| Post-spin | Post-spin-off | The period AFTER a corporate spin-off was completed - i.e., when the business unit operated as an independent public company. For GE Aerospace: 'post-spin' means from April 2, 2024 onward. | — | industry |
| Pre-spin | Pre-spin-off | The period BEFORE a corporate spin-off was completed - i.e., when the business unit was still part of the parent company. For GE Aerospace: 'pre-spin' means before April 2, 2024, when GE Vernova was separated. | — | industry |
| Production Ramp | Production Ramp | Ramp-up phase of a new product generation in manufacturing. | — | memory |
| Q |
| QE | Quantitative Easing | Central-bank bond purchases — expands money supply. | — | macro |
| QLC | Quad-Level Cell NAND | NAND with 4 bits per cell — highest density, lower endurance. Enterprise-SSD standard. | — | memory |
| QoQ | Quarter-over-Quarter | Comparison to the immediately preceding quarter. | — | growth |
| QT | Quantitative Tightening | Central-bank balance-sheet runoff — drains money supply. | — | macro |
| Quick Ratio | Quick Ratio (Acid Test) | (Current assets − inventory) / current liabilities. Stricter than current ratio. | <0.5 tight · 0.5-1 ok · >1 solid | liquidity |
| R |
| R&D | Research & Development | Research and development expense. | — | profitability |
| Reflexivity | Reflexivity (Soros) | Price and fundamentals influence each other — self-reinforcing feedback loops. | — | skill |
| ROA | Return on Assets | Net income / total assets. Asset efficiency. | <3% weak · 3-8% solid · >8% strong | profitability |
| ROE | Return on Equity | Net income / equity. How efficiently does management deploy equity capital? | <8% weak · 8-15% solid · 15-25% strong · >25% premium (watch for book-value gimmicks) | profitability |
| ROIC | Return on Invested Capital | NOPAT / invested capital (equity + interest-bearing debt). Buffett favorite for capital-allocation quality. | <WACC value-destroying · WACC-15% solid · 15-25% strong · >25% wide moat | profitability |
| ROTCE | Return on Tangible Common Equity | Like ROE but excluding goodwill/intangibles. Banking standard. | <10% weak · 10-15% fair · 15-20% good · >20% top tier | profitability |
| RSI | Relative Strength Index | Momentum oscillator 0-100. Measures speed and magnitude of recent price changes. | <30 oversold · 30-50 weak · 50-70 strong · >70 overbought | technical |
| S |
| S-1 | Registration Statement (Form S-1) | IPO filing. | — | format |
| SaaS | Software as a Service | Subscription-based cloud-hosted software. | — | industry |
| SAM | Serviceable Addressable Market | Actually addressable sub-market. | — | industry |
| SBC | Stock-Based Compensation | Equity compensation paid to employees. Dilutes shareholders — should be subtracted from FCF. | <2% of revenue ok · 2-5% watch · >5% problematic | profitability |
| SEC | Securities and Exchange Commission | US securities regulator. | — | format |
| SG&A | Selling, General & Administrative Expenses | Sales, admin, and overhead costs. | — | profitability |
| Sharpe | Sharpe Ratio | Return over risk-free rate divided by volatility. Risk-adjusted return. | <0.5 weak · 0.5-1 ok · 1-2 good · >2 excellent (rarely sustainable) | technical |
| Shop Visit | Shop Visit | Scheduled or unscheduled removal of an aircraft engine from service for inspection, maintenance, or overhaul. The frequency and depth of shop visits drive aftermarket Services revenue. | — | industry |
| Short Interest | Short Interest | Share of float sold short. | <3% low · 3-10% normal · 10-20% elevated · >20% squeeze risk | format |
| SMA | Simple Moving Average | Simple moving average — unweighted mean. | — | technical |
| SPAC | Special Purpose Acquisition Company | Blank-check vehicle for going public. | — | industry |
| Spin-off | Spin-off | A corporate action in which a parent company creates a new independent company by distributing shares of a business unit to its existing shareholders. | — | industry |
| SVP | Senior Vice President | Senior Vice President. | — | industry |
| T |
| TAM | Total Addressable Market | Maximum theoretical market size. | — | industry |
| TLC | Triple-Level Cell NAND | NAND with 3 bits per cell — standard for client SSDs. | — | memory |
| TTM | Trailing Twelve Months | Sum of the last 12 months (rolling, not fiscal year). | — | growth |
| U |
| UNRATE | Unemployment Rate | Unemployment rate (FRED code). | <4% full employment · 4-5% normal · >6% recession | macro |
| UST | US Treasury | US government bond. | — | macro |
| V |
| Variant Perception | Variant Perception | Howard Marks / Druckenmiller principle: where does your view measurably differ from consensus? | — | skill |
| VIX | CBOE Volatility Index | Expected 30-day vol of the S&P 500 (annualized). The 'fear index'. | <12 calm · 12-20 normal · 20-30 nervous · >30 panic | macro |
| VWAP | Volume-Weighted Average Price | Volume-weighted average price of the day. | — | technical |
| W |
| WACC | Weighted Average Cost of Capital | Weighted average cost of capital (equity + debt). Discount rate in a DCF. | 6-8% mega-caps · 8-10% mid-cap · 10-15% small/risk | valuation |
| Wafer | Silicon Wafer | Silicon disc (300mm standard) on which chips are manufactured. | — | memory |
| Wafer Yield | Wafer Yield | Share of functioning chips per wafer. Higher yield = lower cost per chip. | — | memory |
| X |
| XBRL | eXtensible Business Reporting Language | Machine-readable format for SEC data. Backbone of many fundamental-data tools. | — | format |
| Y |
| YoY | Year-over-Year | Comparison to the same period in the prior year (e.g., Q1-26 vs Q1-25). | — | growth |