Join forces in summer get-together (5)

I believe the answer is:

merge

'join forces' is the definition.

'in summer get-together' is the wordplay.
'in' says the answer is hidden in the clue.
'MERGE' is hidden in the letters of 'summer get together'.

(Other definitions for merge that I've seen before include "Combine elements" , "Join into one" , "Mix" , "Blend, coalesce" , "Fuse" .)

I've seen this clue in The Telegraph.

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