Foreword, for short (5)
I believe the answer is:
intro
'foreword for short' is the definition.
(I've seen this in another clue)
This is the entire clue.
(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.)" .)