Least expensive (8)
I believe the answer is:
cheapest
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">least expensive</span>' is the definition.<br/ ><span class="explanation-format__explanation">('cheap' is the opposite of 'expensive' so 'cheapest' should be a synonym for 'least expensive')</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for cheapest that I've seen before include "The space (anag.)" , "Of the poorest quality" , "Most economical" , "Most cut-price" , "Most inferior" .)