Build up a service (5)

I believe the answer is:

amass

'build up' is the definition.
(I've seen this in another clue)

'a service' is the wordplay.
'service' becomes 'mass' (kind of church service).
'a'+'mass'='AMASS'

(Other definitions for amass that I've seen before include "Accumulate over time" , "Accumulate, pile up" , "Stockpile" , "Gather in great quantity" , "Be a compiler" .)

I've seen this clue in The Daily Mail.

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