Happening to find strange company in gambling den (8)

I believe the answer is:

occasion

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'happening' is the definition.
(I know that occasion is a type of happening)

I don't understand the remainder of the clue.

Can you help me to learn more?

(Other definitions for occasion that I've seen before include "Special or formal event" , "Cause - event" , "Special event; reason" , "Provoke" , "Give rise to" .)

I've seen this clue in The Irish Times.

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