【Occurrence】 , 【event】 ,  【incident】 ,  【episode】 ,  【circumstance】  are comparable when they denote something that happens or takes place.

【Occurrence】 is the general term for something which takes place.

【Event】 is frequently regarded as arising from an antecedent state of things and is usually applied to a more or less important or noteworthy 【occurrence】 .

An  【incident】  (compare incidental under ACCIDENTAL ) is commonly an 【occurrence】 of subordinate character or secondary importance, either a mere casual happening having little relation to major events or an 【occurrence】 that merely follows because of them.

The term may, however, be used of a single 【event】 that stands out or is marked off clearly from the other events (as in a story, a play, or a history) in its nature or significance or applied to a critical 【event】 that provokes a break in diplomatic relations between countries or suggests the possibility of war.

【Episode】  (see also DIGRESSION ) is often used in place of  【incident】  in the sense of a single or outstanding 【event】 , but the term usually carries a stronger implication of distinctiveness or apartness from the main course than does  【incident】 .

【Circumstance】  is used as a synonym of  【incident】 only when the latter is thought of as a specific or significant detail. The word is also occasionally used as a synonym for  【event】 in its more general sense.