expounder

1 a person who actively supports or favors a cause an articulate expounder of the liberal position on the issue Synonyms advocate, advocator, apostle, backer, booster, champion, exponent, espouser, friend, gospeler (or gospeller), herald, hierophant, high priest, paladin, promoter, proponent, protagonist, supporter, true believer, tub-thumper, white knightRelated Words loyalist, partisan (also partizan), stalwart; adherent, cohort, disciple, follower; interpreter; applauder, cheerleader, encourager, fellow travelerNear Antonyms enemy, foe, rival; belittler, critic, faultfinderAntonyms adversary, antagonist, opponent

2 one who brings an art or science to full realization one of the early expounders of abstract expressionism Synonyms exponent, guru, high priest, interpreter, practitionerRelated Words dean, doyen, grand old man; ideologue (also idealogue), philosopher, theorist; advocate, apostle, backer, booster, champion, promoter, proponent, supporter