Portion of a larger whole (7)
I believe the answer is:
aliquot
'portion of a larger whole' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for aliquot that I've seen before include "giving exact division" , "Integral factor" , "Chemical sample" , "Portion of a larger whole; to quail (anagram)" , "Of divisor producing quotient without fraction." .)