Some introduced to embellish part of military uniform (7)
I believe the answer is:
lanyard
'part of military uniform' is the definition.
'some introduced to embellish' is the wordplay.
'some' becomes 'any' ('any' can be similar in meaning to 'some').
'introduced to' means one lot of letters goes inside another.
'embellish' becomes 'lard' ('lard' can be a synonym of 'embellish').
'any' placed inside 'lard' is 'LANYARD'.
(Other definitions for lanyard that I've seen before include "Cord with whistle attached" , "Nautical rope" , "Part of rigging" , "Cord worn round neck" , "Dawdler" .)