Trimmed beef for example, knowing it's too small (6)
I believe the answer is:
measly
'small' is the definition.
(thesaurus)
'trimmed beef for example knowing it's too' is the wordplay.
'trimmed' means to remove the last letter (the final letter is trimmed off).
'beef for example' becomes 'meat' (beef is a kind of meat).
'knowing' becomes 'sly' (sly can mean crafty or knowing).
'it's too' is a charade indicator (letters next to each other).
'meat' with its last letter removed is 'mea'.
'mea'+'sly'='MEASLY'
(Other definitions for measly that I've seen before include "on the meagre side" , "Poor" , "Ridiculously small" , "Spotty - paltry" , "Miserable" .)