Refusing to change one's mind (7)
I believe the answer is:
adamant
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">refusing to change one's mind</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for adamant that I've seen before include "Unpersuadable" , "Unshakable (in an opinion)" , "Obdurate and unyielding" , "Insistent, inflexible" , "Impervious to pleas or persuasion" .)