It's full of holes (3)
I believe the answer is:
net
'of holes' is the definition.
The definition suggests a singular noun which matches the answer.
'it's full' is the wordplay.
I cannot really see how this works, but
'it' could be 't' (abbreviation. e.g. in 'tis) and 't' is located in the answer.
The remaining letters 'ne' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for net that I've seen before include "Snare or trap" , "Fish-catcher" , "Open-mesh fabric" , "Overall; mesh" , "Open-meshed fabric" .)