Leave coat beside Irish lake (8)
I believe the answer is:
furlough
'leave' is the definition.
(I know that furlough is a type of leave)
'coat beside irish lake' is the wordplay.
'coat' becomes 'fur' (fur coat is a kind of coat).
'beside' is a charade indicator (letters next to each other) (I've seen this in other clues).
'irish lake' becomes 'lough' (Irish term for 'lake').
'fur'+'lough'='FURLOUGH'
(Other definitions for furlough that I've seen before include "Leave of absence from military duties" , "Temporary leave of absence from military duty" , "Very unattractive" .)