OWL-Time (Time Ontology)

What it is

OWL-Time is an OWL 2 DL ontology for describing temporal properties of resources. It covers ordering relations among instants and intervals, durations, and temporal positions expressed in Gregorian date-time or other temporal reference systems such as Unix time, geologic time, and alternative calendars.

Key concepts

• time:TemporalEntity has the two subclasses time:Interval and time:Instant; beginning, end, duration, and generic time-association properties connect temporal descriptions to entities.
• Allen-style interval relations—such as before, meets, overlaps, during, starts, and finishes—support qualitative ordering and relative-position reasoning.
• time:TRS, time:TimePosition, time:GeneralDateTimeDescription, and time:TemporalUnit support coordinate, ordinal, and calendar-clock representations with explicit reference systems and precision.

How you’d use it

Attach an instant, interval, or duration to an event or other resource, then represent its position with an XSD date-time, a structured date-time description, or a value in a named temporal reference system. Use the interval relations when relative ordering matters more than a single timestamp.

LLM angle

none stated

Pitfalls & lessons

The fetched document is a Candidate Recommendation Draft and says it should be cited as work in progress. Calendar arithmetic is not uniformly exact: Gregorian months have variable length, leap-second handling differs from ISO 8601, detailed time-zone definitions are outside the ontology, temporal vagueness is not addressed explicitly, and time series are out of scope.

Verdict

A broad, reusable temporal vocabulary when data must combine instants, intervals, durations, and non-Gregorian or ordinal reference systems; its stated scope boundaries and draft status should be accounted for.

Sources consulted

• https://www.w3.org/TR/owl-time/