Most unattractive (7)
I believe the answer is:
ugliest
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">most unattractive</span>' is the definition.<br/ ><span class="explanation-format__explanation">('ugly' is associated in meaning with 'unattractive')</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for ugliest that I've seen before include "superlatively unattractive" , "Most unattractive in appearance" , "Most deficient in beauty" , "Most repulsive" , "Least pretty" .)