Decoration from Territorial Army without backing (6)
I believe the answer is:
tassel
'decoration' is the definition.
(tassel is a kind of decoration)
'territorial army without backing' is the wordplay.
'territorial army' becomes 'ta'.
'without' becomes 'less'.
'backing' says the letters should be written in reverse.
'less' reversed gives 'ssel'.
'ta'+'ssel'='TASSEL'
'from' acts as a link.
(Other definitions for tassel that I've seen before include "Decorative tuft of threads" , "Decorative ending to a cord" , "Bunch of cords fastened at one end" , "Ornamental hanging tuft" , "Hanger-on perhaps" .)