A crowd get together (5)

I believe the answer is:

amass

'get together' is the definition.
(I've seen this before)

'a crowd' is the wordplay.
'crowd' becomes 'mass' (massing is a kind of crowding).
'a'+'mass'='AMASS'

(Other definitions for amass that I've seen before include "Accumulate, heap up" , "Build up" , "Gathers" , "store" , "Put together" .)

I've seen this clue in The Telegraph.

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