Tribe supported by good chief (4)
I believe the answer is:
king
'chief' is the definition.
(thesaurus)
'tribe supported by good' is the wordplay.
'tribe' becomes 'kin' ('kin' can be a synonym of 'tribe').
'supported by' says to put letters next to each other (letters go below - in down clue).
'good' becomes 'g' (abbreviation).
'kin'+'g'='KING'
(Other definitions for king that I've seen before include "eg Wenceslas" , "Chesspiece which mustn't be lost" , "Honour for man" , "as Solomon was" , "See 22" .)