Watch found in ladies' pyjamas (4)
I believe the answer is:
espy
'watch' is the definition.
(I've seen this before)
'in ladies' pyjamas' is the wordplay.
'in' indicates the answer is hidden within the clue.
'ESPY' can be found hidden inside 'ladies pyjamas'.
'found' acts as a link.
(Other definitions for espy that I've seen before include "Observe, notice" , "Detect" , "Behold" , "Spot; observe" , "Pick out at a distance" .)