Unimportant predicament? Not at first (5)
I believe the answer is:
light
'unimportant' is the definition.
(I've seen this before)
'predicament? not at first' is the wordplay.
'predicament?' becomes 'plight' ('plight' can be a synonym of 'predicament').
'not at first' means to remove the first letter.
'plight' with its initial letter removed is 'LIGHT'.
(Other definitions for light that I've seen before include "Brightness" , "Radiance" , "answer to clue" , "Falling short of contract" , "Low in density" .)