Laugh when sloshed Hector drinks litre (7)
I believe the answer is:
chortle
'laugh' is the definition.
(I know that chortle is a type of laugh)
'sloshed hector drinks litre' is the wordplay.
'sloshed' is an anagram indicator.
'drinks' indicates putting letters inside.
'litre' becomes 'L' (abbreviation).
'hector' anagrammed gives 'chorte'.
'chorte' enclosing 'l' is 'CHORTLE'.
'when' is the link.
(Other definitions for chortle that I've seen before include "Laugh out loud" , "Titter" , "Chuckle merrily" , "Noisy gleeful laugh" , "Joyous chuckle" .)