Chief sobs uncontrollably (4)
I believe the answer is:
boss
'chief' is the definition.
(synonyms)
'sobs uncontrollably' is the wordplay.
'uncontrollably' indicates anagramming the letters (I've seen this in other clues).
'sobs' is an anagram of 'BOSS'.
(Other definitions for boss that I've seen before include "designer" , "Take charge of" , "Leader - knob on shield" , "Person managing" , "One in charge; stud" .)