Does it not completely cover the floor? (4)
I believe the answer is:
lino
'cover the floor?' is the definition.
Although both the answer and definition are singular nouns, I don't see how they can define each other.
'does it not completely' is the wordplay.
I cannot really understand how this works, but
'not' could be 'no' (negative) and 'no' is found in the answer.
The remaining letters 'li' 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 lino that I've seen before include "put this down?" , "'Floor covering, in short (4)'" , "Floor covering (abbr)" , "Tough floor covering" .)