Sweated (8)
(Other definitions for agonised that I've seen before include "Tormented" , "suffered a lot" , "Felt mental anguish (over a decision)" , "suffered torment" , "experienced pain" .)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">sweated</span>' is the definition.<br/ ><span class="explanation-format__explanation">('perspire' can be a synonym of 'sweat')</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for perspired that I've seen before include "Sweated" , "was sweaty" .)