The getting in early may be hard (8)
I believe the answer is:
leathery
'hard' is the definition.
(thesaurus)
'the getting in early may be' is the wordplay.
'getting in' means one lot of letters goes inside another.
'may be' indicates an anagram.
'early' is an anagram of 'leary'.
'the' put within 'leary' is 'LEATHERY'.
(Other definitions for leathery that I've seen before include "as old balls?" , "Tough like tanned hide" , "Tough textured" , "Like a football" , "(Of skin) having a tough and hard texture" .)