Showing off a chest without a lid (7)
I believe the answer is:
topless
'without a lid' is the definition.
('lid' can be 'top' (I've seen this in another clue) so maybe 'without a lid' can be ''topless')
'showing off a chest' is the wordplay.
I cannot really see how this works, but
'off' could be 'less' (I've seen this in another clue) and 'less' is present in the answer.
The remaining letters 'top' is a valid word which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for topless that I've seen before include "Naked above the waist" , "Bare-breasted" , "Wearing no clothing above the waist" , "Half-naked" , "Leaving the breasts uncovered" .)