Lake swimmer in clip of Endeavour is revealed (5)
I believe the answer is:
trout
'lake swimmer' is the definition.
'trout' can be an answer for 'swimmer' (trout is a kind of fish). I am unsure of the 'lake' bit.
'clip of endeavour is revealed' is the wordplay.
'clip of' means to remove the last letter (I've seen 'clipped' mean this).
'endeavour' becomes 'try' ('try' can be a synonym of 'endeavour').
'is revealed' becomes 'out' (I've seen this before).
'try' with its final letter taken away is 'tr'.
'tr'+'out'='TROUT'
'in' is the link.
Can you help me to learn more?
(Other definitions for trout that I've seen before include "Tasty fish, perhaps of rainbow kind" , "unpleasant old woman" , "Tasty fish, brown or rainbow" , "bad-tempered woman" , "old bag" .)