Learn the meaning of occasion as a noun and a verb, with synonyms, idioms and usage examples. Find out how to use occasion in different contexts and situations. Occasion definition : a particular time, especially as marked by certain circumstances or occurrences.. See examples of OCCASION used in a sentence. Occasion is a noun that means an event, a time, a reason, or an opportunity. Learn how to use it in different contexts and idioms, and see synonyms and translations. Occasion definition : An event or happening, or the time of an event or happening.