Leave coat found on lake (8)
I believe the answer is:
furlough
'leave' is the definition.
(furlough is a kind of leave)
'coat found on lake' is the wordplay.
'coat' becomes 'fur' (fur is a kind of coat).
'found on' means one lot of letters go next to another.
'lake' becomes 'lough' (lough is a kind of lake).
'fur'+'lough'='FURLOUGH'
(Other definitions for furlough that I've seen before include "Leave of absence from military duties" , "Very unattractive" , "Temporary leave of absence from military duty" .)