Plain writing (5)
I believe the answer is:
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">plain writing</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for prose that I've seen before include "Ordinary spoken or written language" , "Normal written language" , "Ropes (anag.)" , "Non-verse" , "Ordinary writing" .)