Open late to make a buck (8)
I believe the answer is:
antelope
'a buck' is the definition.
(thesaurus)
'open late to make' is the wordplay.
'to make' indicates an anagram.
'open'+'late'='openlate'
'openlate' anagrammed gives 'ANTELOPE'.
(Other definitions for antelope that I've seen before include "it runs very quickly" , "Springbok, perhaps" , "Odd toe panel of this hoofed animal" , "Horned ruminant" , "A graceful gazelle from Africa" .)