Informal get-together regularly seems to take hours (4)

I believe the answer is:

sesh

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'informal get-together' is the definition.
I don't know anything about this answer so I can't judge whether it can be defined by this definition.

'regularly seems to take hours' is the wordplay.
'regularly' indicates alternate letters (regularly take one letter, leave next etc.).
'to take' is a charade indicator (letters next to each other).
'hours' becomes 'h'.
The alternate letters of 'seems' are 'ses'.
'ses'+'h'='SESH'

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(Other definitions for sesh that I've seen before include "Sitting" , "lots of drinks?" .)

I've seen this clue in The Independent.

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