Porridge (5)
I believe the answer is:
gruel
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">porridge</span>' is the definition.<br/ ><span class="explanation-format__explanation">(gruel is a kind of porridge)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for gruel that I've seen before include "Unappetising food" , "cheap fare" , "Thin oatmeal dish" , "Thin porridge" , "Thin food of boiled oatmeal" .)