Glossary

Find definitions for the market, trading, identity, clearing, and API terms used throughout the UDX REST and WebSocket documentation.

UDX uses the same terms across REST, WebSocket, and FIX.

Term	Definition
Account	A position-bearing account under one member.
API Key	A credential issued for programmatic access on behalf of a user, with explicit scopes and an optional restriction to one account.
Combo	A synonym for a multi-leg market.
Contract	The unit traded in a market. One YES contract pays $1 when the market settles YES and $0 when it settles NO. Quantities can use increments of `0.01`.
DCM	Designated Contract Market. The exchange side of UDX that lists markets, runs order books, and matches orders into trades.
DCO	Derivatives Clearing Organization. The clearing side of UDX that holds positions and balances and settles markets.
Event	A real-world proposition with a binary YES or NO outcome.
Grant	A user’s authorization to act on one specific account belonging to that user’s member.
Idempotency Key	An optional client-generated token on a mutating request. Resending an identical keyed request replays the original response rather than executing again. Reusing a key with a different request is rejected.
L1	Top-of-book market data: best bid and ask with aggregate size, without deeper price levels or last-trade information.
L2	Market-by-price data: the full price ladder with quantity aggregated at each level.
L3	Market-by-order data: every individual resting order and its queue position.
Market	A tradable binary contract whose settlement direction derives from one or more event outcomes. Each market has one order book.
Market Catalog	The published set of single-leg and multi-leg markets with their metadata. It is served live and never cached, because a market’s trading status rides with it.
Market Data	Published order-book views at L1, L2, or L3 depth, plus trading activity such as trades and statistics.
Market Lifecycle	The trading statuses a market moves through, from `unopened` to `expired`, and the settlement that follows.
Market Metadata	A market’s descriptive and trading parameters: ticker, description, status, tick size, price bounds, and expiration.
Market Statistics	A market’s trading-activity summary, such as volume and open interest, as distinct from its order book.
Member	A participant that owns users and accounts. REST request capacity is shared at the member level.
Multi-leg Market	A market combining the selected outcomes of two or more component markets. Also known as a combo.
Order	An instruction to buy or sell YES contracts in one market at specified terms. Resting orders make up its order book.
Order Book	The resting buy YES and sell YES orders for a market, organized by price and queue position.
Outcome	The resolved YES or NO result of an event.
Position	An account’s signed net quantity of YES contracts in a market: positive is long and negative is short.
Quote	A single-sided bid or offer answering an RFQ.
Resolution	Determining an event’s YES or NO outcome from external evidence. Resolution occurs before dependent markets can settle.
RFQ	A request for quote: a solicitation for quotes in one market or a set of legs.
RFQ Participant ID	The identifier a user is known by to RFQ counterparties.
Series	A recurring family of events.
Settlement	Applying the resolved outcomes of one or more events to a market’s positions and crediting the winning side.
Single-leg Market	A market whose settlement direction derives from one event outcome.
Trade	An execution created when compatible buy and sell orders match.
Transfer	An atomic movement of funds between two accounts of the same member.
User	A human or programmatic identity that authenticates and acts for a member through one or more grants.
YES Contract	The single contract traded in a market. Buying goes long YES; selling goes short YES. There is no separate NO contract.