Quiet, small reserve receiving 75% of grant (7)
I believe the answer is:
silence
'quiet' is the definition.
(synonyms)
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for silence that I've seen before include "What's left of burnt coal" , "Quiet" , "that's golden" , "'The rest is - - '(Hamlet)" , "License (anag)" .)