Part of problem in ironing dress (4)
I believe the answer is:
mini
'dress' is the definition.
(mini dress)
'part of problem in ironing' is the wordplay.
'part of' says the answer is hidden in the clue.
'MINI' is hidden in the letters of 'problem in ironing'.
(Other definitions for mini that I've seen before include "Baby" , "Short skirt - small car" , "Small (of car, skirt, disk,bar or series)" , "Brief" , "Cult British car" .)