Glossary

A working glossary of every term you need to read, trade, or talk about prediction markets — from YES share to CFTC to UMA oracle.

Updated

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Glossary

Position

Your current holding in a market — the number of YES or NO shares you own and their cost basis.

Glossary

Market order

An order to trade immediately at whatever prices are currently available on the book.

Glossary

Limit order

An order to buy or sell only at a specified price or better. Will not fill if the market doesn't reach your price.

Glossary

Fill

Confirmation that some or all of your order has executed at a specific price.

Glossary

Slippage

The difference between the price you expected to trade at and the price you actually got.

Glossary

Event contract

The legal term for a Kalshi-style binary derivative that pays $1 if a specific real-world event occurs.

Glossary

CFTC

The Commodity Futures Trading Commission — the US regulator that oversees Kalshi and other licensed event-contract exchanges.

Glossary

KYC

Know-Your-Customer: the ID and address verification a regulated exchange must do before letting you trade.

Glossary

Withdrawal

Moving cash off a prediction-market platform back to your bank or wallet.

Glossary

Fee

The platform's cut on a trade, withdrawal, or settlement. Eats into edge — calculate before sizing positions.

Glossary

Scalar market

A market that resolves to a number on a continuous range rather than a yes/no — e.g. final SAT score or acceptance rate.

Glossary

Categorical market

A market with more than two mutually-exclusive outcomes — e.g. which candidate wins, or which school takes the top ranking.