Travel metasearch glossary
A technical reference for distribution, pricing, identity, APIs, tracking, resilience and travel-search terminology. Every term links to its own entity page, related concepts and technical guides.
A
ARI
Distribution of hotel availability, rates and inventory state. Reliable ARI depends on change detection, idempotency and reconciliation.
Explore →Availability
Whether an offer is actually sellable for a given date, occupancy and product context. A price alone does not guarantee availability.
Explore →Attribution
Model assigning booking credit to clicks, sessions, campaigns or sources. Last-click attribution misses assisted influence in multi-touch travel journeys.
Explore →Assisted Conversion
A channel or interaction that contributes to booking without being the final click. It matters in journeys such as OTA research followed by direct booking.
Explore →API
A request/response or action contract between systems. In travel, latency, rate limits, retry behavior and idempotency are part of the operational contract.
Explore →Agent
The airline, OTA or provider selling a flight offer. The same itinerary can be sold by multiple agents with different prices and conditions.
Explore →Agency Model
A model where the traveler typically pays the supplier and the intermediary earns commission.
Explore →Attribution Window
The period during which a click or interaction remains eligible for attribution to a downstream booking.
Explore →Ancillary
An optional service added to the core travel product, such as baggage, seats, lounge access or priority. Its identity and eligibility should survive booking and servicing.
Explore →Authorization
The payment step that approves or reserves a chargeable amount on a payment method. Successful authorization does not imply capture or booking confirmation.
Explore →Agentic Commerce
A commerce model where an AI agent interacts with structured commerce systems for discovery, selection, checkout or transactions on a user's behalf. Authorization, auditability and deterministic transaction boundaries are core concerns.
Explore →A2A
An open protocol aimed at capability discovery, task delegation and interaction between independent agents. It addresses a different layer from MCP, which focuses on tool/resource access.
Explore →ACP
An open commerce standard for merchant catalogs, checkout and agent-mediated purchasing. It lets agents transact through structured commerce contracts while merchants retain control of checkout and payment systems.
Explore →AP2
An open payment-authorization protocol for proving user authority and transaction intent in agent-performed payments through verifiable mandates. It is not itself a commerce protocol; it focuses on the payment trust and authorization layer.
Explore →B
Base Rate
The base price before taxes, mandatory fees or other components. Confusing it with total price creates price-accuracy problems.
Explore →Backoff
A strategy that increases delay between retry attempts. It helps prevent retry storms during rate limits or upstream outages.
Explore →Booking Engine
System managing availability, rate, guest, payment and confirmation. Metasearch deep links should preserve the correct context into it.
Explore →Bedbank
A B2B accommodation wholesaler that contracts hotel inventory and redistributes it to OTAs, tour operators and other resellers.
Explore →Bulkhead
A resilience pattern that isolates resources so one provider or workload failure does not cascade to others.
Explore →C
Canonical ID
A stable internal identifier that survives supplier or channel changes. Channel-specific IDs should map into the canonical model through adapters.
Explore →Commission
Revenue share paid to a distribution channel, often based on booking value. Gross commission and post-cancellation net commission should be tracked separately.
Explore →CPC
Cost incurred per offer click. Efficiency should be read together with click-to-book conversion and net booking value, not CPC alone.
Explore →CPA
Cost per defined acquisition or booking. Attribution windows and cancellation policy materially affect interpretation.
Explore →CPS
Cost tied to a completed sale. In travel, the sale definition may mean confirmed, stayed or non-cancelled booking.
Explore →CTR
Share of impressions that generate a click. CTR alone is not quality and should be interpreted with downstream conversion.
Explore →Conversion Rate
The booking rate from a defined funnel step. Its meaning changes depending on whether the denominator is search, detail view or provider click.
Explore →Conversion Tracking
Measurement of bookings, cancellations and revenue after a click. Stable click IDs and reconciliation are essential to channel economics.
Explore →Catalog
A normalized product/entity view built by an advertising or distribution platform from feeds. A correct source feed can still produce a bad catalog through mapping rules.
Explore →Changed Pricing
Approach where the partner signals changed pricing so the platform refreshes relevant contexts. Change-detection quality drives stale-price risk.
Explore →Cache Hit Ratio
Share of requests served from cache rather than upstream calls. A high hit ratio is useful only when it does not increase stale data.
Explore →Circuit Breaker
A resilience pattern that temporarily stops calls to failing or slow upstream services. It limits search latency and cascading failures.
Explore →Carrier
The airline marketing or operating a flight. Carrier identity should not be confused with booking-agent identity.
Explore →CRS
A system that centrally manages hotel inventory, rate plans, availability and reservations. It can act as an important source-of-truth layer between PMS, channel managers, booking engines and distribution channels.
Explore →Channel Manager
A distribution layer synchronizing hotel rates, availability and inventory across multiple OTAs and channels.
Explore →CTA
A restriction preventing check-in on a specific date.
Explore →CTD
A restriction preventing check-out on a specific date.
Explore →Conditional Rate
A rate available only to users meeting membership, mobile, geography, loyalty or campaign conditions.
Explore →Contribution Margin
The economic contribution remaining after channel acquisition, commission, payment, servicing and relevant variable costs are deducted from revenue.
Explore →Capture
The act of collecting or submitting for settlement an amount that was previously authorized. Booking and payment should be tracked as separate state machines.
Explore →Compensation
A business action that reverses the effect of a completed step in a distributed workflow, such as voiding a payment authorization after booking failure.
Explore →D
Deep Link
A URL that sends the traveler into booking with the selected product and search context. Dates, occupancy, currency and attribution should be preserved where possible.
Explore →Direct Booking
Booking completed through the supplier's own channel. Direct offers in metasearch need comparable semantics against OTA offers.
Explore →Derived Rate
A rate whose price is derived from another rate plan using fixed or percentage adjustments.
Explore →Delegated Payment
Secure delegation of payment credentials or spending authority into an agent/merchant flow with constraints such as amount, expiry and permitted use.
Explore →F
Feed
Bulk or scheduled machine-readable data transfer between systems. Production feeds require schema discipline, versioning, idempotency, validation and observability.
Explore →Freshness
How closely data reflects current source state. Different data domains require different TTL and freshness objectives.
Explore →Fare Family
A branded flight product bundling baggage, seat, change/refund and ancillary rights. Normalizing only the numeric price can erase meaningful fare-family differences.
Explore →Fulfillment
Delivery of the purchased travel value as a ticket, voucher, confirmation or other usable entitlement.
Explore →G
H
Hotel List
Static property master data supplied to a distribution platform. Stable IDs, address, geo and active state are foundational to matching quality.
Explore →Human-in-the-Loop
A control model where an agent workflow pauses for human approval, review or decision at a critical step. It can serve as an authority boundary for high-impact booking, payment or cancellation actions.
Explore →I
Inventory
Sellable room, seat or vehicle capacity. Inventory must be interpreted together with restrictions, allotments and stop-sell rules.
Explore →Indicative Price
An approximate or aggregated price signal used for flexible-date or destination discovery. Live repricing is needed closer to booking.
Explore →Idempotency
The property that repeated updates or conversion events do not corrupt state. It is critical in feed retries and booking-event pipelines.
Explore →Itinerary
A flight journey composed of legs and segments. Pricing options are commonly defined in itinerary-plus-agent context.
Explore →Idempotency Key
A stable request key used to prevent the same logical mutation from being applied twice on retry. It is critical for side-effecting operations such as booking, payment and order creation.
Explore →L
Look-to-Book
Ratio of searches or lookups to bookings. It is critical for supplier API capacity planning and cache strategy.
Explore →Landing Page
The provider or booking page opened after a metasearch click. HTTP 200 alone is insufficient; product and price context must also be preserved.
Explore →Live Price
A current provider-backed price for high-intent search. It has different freshness expectations from an indicative price.
Explore →Latency Budget
The response-time allocation for each supplier or service in an end-to-end search. Timeouts and progressive results should be designed around it.
Explore →Leg
An origin-to-destination direction within an itinerary, such as outbound or return. A leg may contain multiple segments.
Explore →M
Markup
Commercial uplift applied over a supplier net rate. It may vary by market, channel, product or campaign and affects parity and ROAS analysis.
Explore →Metasearch
A distribution layer that normalizes and compares offers from multiple providers in one search context. Identity, freshness, ranking and handoff are core technical problems.
Explore →Merchant of Record
The entity accepting customer payment through its merchant account and carrying primary payment-record, chargeback and refund responsibility.
Explore →Merchant Model
A commercial model where the intermediary charges the traveler and settles a contracted or net amount with the supplier.
Explore →MinLOS
A restriction defining the minimum number of nights accepted for a given arrival/date/rate context.
Explore →MaxLOS
The maximum stay length permitted for a rate or date context.
Explore →Matured Booking
A booking considered commercially more settled after enough cancellation/refund exposure has passed.
Explore →MCP
An open protocol for AI applications to interact with tools, resources and context providers through a standard interface. It is not a commerce or payment protocol; it is a capability-access layer for agents.
Explore →MPP
An open protocol standardizing machine and agent payments inside HTTP request flows through payment challenges, credentials and receipts. It is designed to be payment-method agnostic.
Explore →Mandate
A structured authorization artifact proving which actions, amounts, merchants or conditions an agent is allowed to act within. In agentic payments it provides explicit authority instead of inferred intent.
Explore →N
O
OTA
An online travel intermediary that exposes inventory and often owns much of the booking transaction. The distinction from metasearch is largely about acquisition and transaction ownership.
Explore →Occupancy Pricing
A pricing model where amounts vary by adult/child counts, child ages or room occupancy.
Explore →Offer Fingerprint
A stable comparison identity representing offer semantics such as property/itinerary, occupancy, room/fare, meal, cancellation, eligibility and currency.
Explore →Offer
A sellable commercial proposal combining itinerary/property, price, availability, seller and conditions. Offer identity should retain its source reference through repricing and booking.
Explore →Order
The commercial record that tracks product, traveler, payment and servicing state after purchase. In flight/NDC systems, an order is not the same thing as a PNR or ticket.
Explore →P
POI Feed
A feed model describing physical properties or businesses with location and metadata. It can serve as the property-identity layer in hotel aggregation.
Explore →Property Mapping
Determining whether records from different sources represent the same physical property. Bad mapping can attach an otherwise correct rate to the wrong hotel.
Explore →Price Coverage
The share of searchable hotel/date/occupancy or route/date contexts for which pricing is available. Drops can signal connectivity or inventory issues.
Explore →Price Accuracy
Consistency between the displayed metasearch rate and downstream booking rate. Taxes, fees, currency and occupancy semantics often cause mismatches.
Explore →Package Holiday
A bundled travel product combining at least two travel services in one package context. Component identity, package price and cancellation state need joint management.
Explore →Provider
The party supplying an offer or completing the booking. Provider ranking can depend on reliability and conversion quality as well as price.
Explore →Pull Pricing
Pricing model where the platform requests required rates at query time. Upstream latency and concurrency capacity become critical.
Explore →PMS
The core hotel operations system managing reservations, room assignments, check-in/out, folios and guest state.
Explore →Price Observation
A price observed for a specific query context and timestamp, stored with amount, currency, source, observedAt and freshness metadata.
Explore →PNR
A reservation record containing passenger and itinerary information. A PNR can represent booking state but is not proof of ticket issuance or payment settlement.
Explore →Polling
A method of discovering state changes by periodically querying an API instead of waiting for events. Poll interval, rate limits and eventual consistency should be designed together.
Explore →R
Rate Plan
Commercial rules defining cancellation, meals, payment, eligibility and promotions. Multiple rate plans can exist for the same room type.
Explore →Room Type
The accommodation product class within a hotel. Stable room identity and occupancy semantics matter more than display names during mapping.
Explore →Rate Parity
Price alignment of genuinely comparable hotel offers across channels. Parity is misleading unless room, meal, cancellation and tax differences are normalized.
Explore →ROAS
Revenue generated relative to ad spend. Versions based on net revenue or margin can be more useful than gross booking value.
Explore →Reconciliation
Matching clicks, bookings, modifications, cancellations and payments across systems. It keeps performance reporting aligned with commercial reality.
Explore →Reprice
Validation of a previously observed offer against current price, availability and commercial conditions closer to booking.
Explore →Rate Limit
The request or capacity quota accepted by an API provider within a time window.
Explore →Refund
A full or partial return of a completed payment to the customer. In travel, refund state should be reconciled across supplier, seller and PSP systems.
Explore →S
Seller of Record
The entity shown as seller in the customer contract and carrying the transaction's contractual seller identity. It does not have to be the Merchant of Record.
Explore →Supplier
A hotel, airline, wholesaler, GDS or other inventory source. Supplier contracts are evaluated through availability, rate semantics, latency and commercial terms.
Explore →Stale Price
A rate that remains outdated in metasearch or cache after changing at the source. It creates post-click mismatch and conversion loss.
Explore →Segment
A physical flight operation between one departure and arrival. Marketing and operating carriers can differ.
Explore →Stale-While-Revalidate
A caching pattern that serves recently cached data immediately while refreshing it in the background.
Explore →Servicing
The post-booking lifecycle covering changes, cancellations, reissues, refunds and support. Strong search/booking APIs do not compensate for weak servicing capabilities.
Explore →Saga
A workflow pattern for multi-service operations that cannot fit into one ACID transaction, using steps and compensating actions. It is useful for distributed travel flows such as booking plus payment.
Explore →T
Total Price
The total mandatory amount payable by the traveler, including applicable taxes and fees. Nightly rate and total price are not interchangeable.
Explore →Travel Marketplace
A platform model combining multiple travel verticals, suppliers and transaction models in one consumer-facing retail surface. It may include comparison without being pure metasearch.
Explore →Tour Operator
A distribution role that contracts and combines accommodation, transport, transfers or other travel services into a packaged product.
Explore →TTL
How long cached data can be used before refresh. TTL should reflect booking intent, supplier latency and change volatility.
Explore →Ticket
The document or electronic record representing the right to air transport. An order can be confirmed while ticket issuance is still pending.
Explore →Ticketing
The lifecycle that turns a confirmed flight order into ticket document/coupon state and later manages void, exchange or refund operations.
Explore →U
Unknown Outcome
A state where a timeout or connection loss makes it unclear whether the upstream action completed. UNKNOWN should not be treated as FAILED without lookup or reconciliation.
Explore →UCP
An open protocol for standardizing commerce interactions such as capability negotiation, checkout and order flows across platforms, businesses and payment providers.
Explore →V
W
Wholesaler
A B2B intermediary that acquires travel inventory under contracted or net terms and resells it to other channels.
Explore →Webhook
A server-to-server HTTP callback that pushes state changes to another system. Delivery, ordering, retries and signature verification are part of the production contract.
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