Outfit used in Morse transmissions? (3)
I believe the answer is:
set
'outfit' is the definition.
(setting is a kind of outfiting)
'in morse transmissions?' is the wordplay.
'in' says the answer is hidden in the clue.
'SET' is hidden in the letters of 'morse transmissions'.
'used' acts as a link.
(Other definitions for set that I've seen before include "Badger's burrow" , "Create a puzzle" , "Customary < scenery < a TV < series" , "Become solid like jelly" , "Place - become rigid - adjust - group of tennis games - fixed - clique - fall beneath the horizon" .)