Accumulate a large amount (5)

I believe the answer is:

amass

'accumulate' is the definition.
(synonyms)

'a large amount' is the wordplay.
'large amount' becomes 'mass' (I've seen this in another clue).
'a'+'mass'='AMASS'

(Other definitions for amass that I've seen before include "Stockpile" , "Assemble" , "Accumulate, heap up" , "Stock up on" , "Be a compiler" .)

I've seen this clue in The Times.

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