Always severely trimmed! (4)
I believe the answer is:
ever
'always' is the definition.
(synonyms)
'severely trimmed' is the wordplay.
'trimmed' says the answer is hidden in the clue (part of the clue must be trimmed away).
'EVER' is hidden within 'severely'.
(Other definitions for ever that I've seen before include "Perpetually" , "Eternity" , "Continuously" , "At all times, always" , "Veer away endlessly" .)