Upset relatives sobbing, clutching head (4)
I believe the answer is:
boss
'head' is the definition.
(synonyms)
'upset relatives sobbing clutching' is the wordplay.
'upset' says the letters should be written in reverse.
'clutching' says the answer is hidden in the clue.
'ssob' can be found hidden inside 'relatives sobbing'.
'ssob' reversed gives 'BOSS'.
(Other definitions for boss that I've seen before include "designer" , "Leader - knob on shield" , "27 [CHIEF]" , "(One's) chief" , "Person in charge - raised knob" .)