Throw out bread that's hard (8)
I believe the answer is:
obdurate
'hard' is the definition.
(thesaurus)
'throw out bread' is the wordplay.
'throw' indicates an anagram.
'out'+'bread'='outbread'
'outbread' anagrammed gives 'OBDURATE'.
'that's' is the link.
(Other definitions for obdurate that I've seen before include "A doubter being stubborn" , "uncommonly tough" , "Stubbornly resistant" , "Dogged" , "Unyielding - cruel" .)