Our steel tempered and unyielding (8)
I believe the answer is:
resolute
'unyielding' is the definition.
'our steel tempered' is the wordplay.
'tempered' indicates an anagram (temper can mean to adjust or modify).
'our'+'steel'='oursteel'
'oursteel' is an anagram of 'RESOLUTE'.
'and' is the link.
(Other definitions for resolute that I've seen before include "Determined or decided" , "without flinching" , "Reels out (anag.)" , "Showing great determination, fully committed" , "'Determined, dead set on (8)'" .)