Foreword, for short (5)
I believe the answer is:
intro
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">foreword for short</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 intro that I've seen before include "Song's opening" , "Early music piece" , "First bars of a piece of popular music" , "Lead-in" , "Preliminary section (of music) (colloq.)" .)