Can’t see? Remove top, see inside, it’s full of oil (7)
I believe the answer is:
linseed
'oil' is the definition.
(I've seen this before)
'can't see? remove top see inside it's full' is the wordplay.
I cannot quite see how this works, but
'see?' could be 'see' (seeing is a kind of seeing) and 'see' is located in the answer.
'inside' could be 'in' and 'in' is present in the answer.
This explanation may well be incorrect...
'of' is the link.
Can you help me to learn more?
(Other definitions for linseed that I've seen before include "Oil applied to cricket bats" , "Oil produced from flax" , "Enisled (anag.)" , "Oil producer" , "Type of oil" .)