Crypto Trading Bot Glossary: 60 Terms Builders Must Know

Whether you are commissioning your first trading-bot services or deep in the weeds reviewing a spec sheet, shared vocabulary is the difference between a productive conversation and an expensive misunderstanding. This crypto trading bot glossary covers the 60 terms that appear most often across sniping, MEV extraction, market-making, and the infrastructure layer beneath all of it.

Sniping and Mempool Mechanics

Mempool — The waiting room for unconfirmed transactions on EVM chains. Bots monitor it to front-run large swaps or token launches.

Sniping — Buying a token in the same block (or the first available slot) as a liquidity-add event. Precision at the millisecond level separates a snipe from a miss.

Jito bundles — On Solana, Jito allows groups of transactions to be submitted as an atomic bundle to validator block engines. Bundles guarantee ordering and atomicity, making them the standard vehicle for MEV-sensitive strategies. See how this plays out in practice in our Solana sniper bot case study.

Priority fee — An additional lamport-denominated tip paid to Solana validators to move a transaction higher in the block schedule. Tuning this dynamically is central to any competitive sniping setup.

Geyser stream — Solana's plugin interface for streaming raw account updates and transaction data from a validator in real time. It is the lowest-latency data path available and the foundation of serious on-chain monitoring.

Block engine — The component, often operated by MEV infrastructure providers like Jito Labs, that aggregates bundles and orders them within a block for maximum searcher and validator revenue.

MEV (Maximal Extractable Value) — Profit captured by reordering, inserting, or censoring transactions within a block. Encompasses arbitrage, liquidations, and sniping.

Sandwich attack — A form of MEV where a bot places one transaction before and one after a target swap to profit from the price impact.

Anti-rug simulation — Pre-execution simulation that checks token contract bytecode and LP lock status to reject honeypot or rug-pull contracts before a snipe fires.

Slippage tolerance — The maximum acceptable deviation between expected and executed price. Set too wide and MEV bots exploit it; set too tight and legitimate trades revert.

Compute units (CU) — Solana's measure of transaction complexity. Declaring the correct CU limit avoids failed transactions and reduces wasted priority fees.

RPC node — A remote procedure call endpoint that proxies requests to a blockchain node. Latency between your bot and its RPC endpoint directly caps maximum execution speed.

Market-Making Jargon

CLOB (Central Limit Order Book) — A price-time-priority matching engine where resting limit orders are filled against incoming market orders. Hyperliquid operates a fully on-chain CLOB, which is unusual at L1 throughput.

Inventory skew — Deliberate asymmetry in bid/ask quote sizes or prices to reduce net delta exposure. A market maker long too much of an asset widens its ask and tightens its bid to offload passively.

Spread — The difference between the best bid and best ask. Market makers earn the spread in exchange for providing liquidity and bearing inventory risk.

Mid-price — The arithmetic or volume-weighted average of the best bid and ask, used as a neutral reference for quoting.

Quote refresh rate — How frequently a market-making bot cancels and resubmits its orders. On Hyperliquid, sub-100ms refresh is achievable without gas overhead.

Fill rate — The proportion of maker orders that are actually executed. Low fill rates mean capital is tied up but earning nothing.

Adverse selection — The tendency for limit orders to be filled disproportionately by informed traders who already know the price is about to move against you.

Funding rate — On perpetual futures, the periodic payment between longs and shorts that keeps the perpetual price anchored to spot. Market makers on Hyperliquid track funding to decide which side of the book to lean.

Delta neutrality — A portfolio state where gains and losses from price moves cancel out because hedged positions offset directional exposure.

Maker rebate / taker fee — Exchanges often pay rebates to orders that add liquidity (makers) and charge fees to orders that remove it (takers). Fee tier awareness drives strategy profitability.

Depth of book — The cumulative quantity available at each price level. Thin books amplify slippage on larger orders.

Arbitrage and Cross-Venue Infrastructure

Cross-venue arb — Exploiting price discrepancies for the same asset across two or more exchanges simultaneously. Latency parity between venues is the hard constraint. Our cross-venue arbitrage build illustrates the infra requirements.

Funding rate arb — Going long spot and short perpetual (or vice versa) when funding diverges enough from the cost of carry to generate risk-adjusted yield.

Statistical arb (stat arb) — Using historical correlation between assets to trade mean reversion. Requires a signal model, not just a latency edge.

Basis trade — The spread between a spot price and a futures or perpetual price for the same underlying.

Execution latency — End-to-end time from signal generation to order acknowledgment. Every microsecond of latency is a structural disadvantage in competitive arb.

Co-location — Physically hosting trading servers in the same data center as an exchange's matching engine to minimize round-trip time.

WebSocket feed — A persistent, bidirectional connection for streaming market data. Preferable to REST polling for any latency-sensitive strategy.

Order routing — Logic that decides which venue, pool, or route to send an order through to achieve best execution across fragmented liquidity.

Prediction Market and Resolution Logic

Polymarket — A decentralized prediction market on Polygon where users trade binary outcome contracts (YES/NO) on real-world events.

Resolution — The moment an outcome is determined and winning shares pay out. Bots that price contracts near resolution must account for oracle latency and dispute windows.

Binary contract — A contract that settles at $1 (winner) or $0 (loser). Pricing these requires a probability estimate, not a price level.

Liquidity provision (Polymarket) — Posting resting orders on both sides of a market to earn spread. Risk is correlated with outcome uncertainty rather than price volatility.

Implied probability — The market price of a YES share expressed as a probability. Arb opportunities appear when two correlated markets show inconsistent implied probabilities.

UMA oracle — The dispute-resolution mechanism used by Polymarket for settling ambiguous outcomes. Understanding its latency and dispute window is critical for bots that hold positions into resolution.

Bot Infrastructure and Risk Controls

Kill switch — A hardware or software circuit-breaker that halts all open orders and positions when a predefined drawdown, error rate, or anomaly threshold is breached. Non-negotiable in any production system.

Position limit — A hard cap on gross or net exposure per asset, enforced programmatically to prevent runaway accumulation during adverse market conditions.

Heartbeat — A periodic signal a bot sends to a monitoring service to confirm it is alive. Missed heartbeats trigger alerts or automated restarts.

Paper trading / simulation mode — Running strategy logic against live market data without submitting real orders. Essential for validating logic changes before deploying capital.

Backtest — Replaying a strategy against historical data to estimate performance. Prone to overfitting; walk-forward validation and out-of-sample testing reduce this risk.

Drawdown — Peak-to-trough decline in account value. Maximum drawdown over a backtest period is a standard risk metric.

Sharpe ratio — Risk-adjusted return: mean return divided by standard deviation of returns. Useful for comparing strategies with different volatility profiles.

Alpha decay — The erosion of a strategy's edge over time as more capital chases the same opportunity or the market structure changes.

Gas / fee budget — The pre-set maximum a bot will spend on transaction fees per trade or per time window, preventing fee costs from exceeding strategy returns in volatile conditions.

Nonce management — On EVM chains, correct sequencing of the transaction nonce is required to prevent stuck or replaced transactions. Bots must track nonce state carefully under high throughput.

Circuit breaker — Broader than a kill switch — can pause quoting during abnormal spread events, API outages, or flash crashes while leaving existing positions intact.

Vault architecture — Separating hot trading wallets (small balances, high activity) from cold vaults (bulk capital) to limit exposure from a compromised signing key.

Webhook alert — An HTTP callback sent to an external endpoint (Telegram, Slack, PagerDuty) when a bot event requires human attention.

Rate limit — Exchange API throttles on request frequency. Exceeding them causes rejected orders or temporary IP bans; good bots implement token-bucket logic to stay within bounds.

Order idempotency — Designing order submission so that re-sending a request due to a network timeout does not create duplicate positions.

Deterministic replay — The ability to reproduce past bot behavior exactly, using logged market data and random seeds. Critical for debugging production incidents.

Strategy isolation — Running each strategy in its own process or container so that a crash or resource spike in one does not affect others.

On-chain event listener — A service that subscribes to smart contract events (mint, swap, transfer) and triggers bot logic in response.

Copy-trading — Automatically mirroring the on-chain trades of a target wallet or trader, with configurable size scaling and delay thresholds.

---

Building systems that combine many of these concepts is exactly what we do. If you are ready to move from terminology to implementation, start a project with TierZero and let us scope the right architecture for your strategy.