Not very quiet birdhouse – it's full of bees (6)
I believe the answer is:
apiary
'bees' is the definition.
Although both the answer and definition are nouns, they are not in the same form of the noun. However, I know that 'bees' relates to this answer.
'not very quiet birdhouse it's full of' is the wordplay.
'not' is a deletion indicator.
'very' becomes 'v' (abbreviation).
'quiet' becomes 'p' (music symbol for 'piano', ie soft or quiet).
'birdhouse' becomes 'aviary' (I've seen this in another clue).
'it's full of' means one lot of letters goes inside another.
'p' going within 'aviary' is 'avpiary'.
'avpiary' with 'v' taken away is 'APIARY'.
Can you help me to learn more?
(Other definitions for apiary that I've seen before include "Bee colony" , "Place where bees are kept in hives" , "Bee hive" , "Home for the honey bee" , "Place to keep bees" .)