Assimilate some catering establishments (6)
I believe the answer is:
ingest
'assimilate' is the definition.
(synonyms)
'some catering establishments' is the wordplay.
'some' says the answer is hidden in the clue (some parts of the word are used).
'INGEST' is hidden within 'catering establishments'.
(Other definitions for ingest that I've seen before include "take in, eat" , "Absorb mentally" , "How to take courses" , "Take nourishment into the body" , "Gets in (anag.)" .)