Trims twirling officer's coat decoratively (6)
I believe the answer is:
stucco
'coat decoratively' is the definition.
(to coat with stucco plaster)
'trims twirling officer's' is the wordplay.
'trims' becomes 'cuts' ('cut' can be a synonym of 'trim').
'twirling' says the letters should be written in reverse.
'officer' becomes 'co' (Commanding Officer abbreviation).
'cuts' written backwards gives 'stuc'.
'stuc'+'co'='STUCCO'
(Other definitions for stucco that I've seen before include "Plaster for decorative work" , "Durable finish for walls" , "Fine decorative plaster" , "wall-covering" , "White plaster covering for exterior walls" .)