Englishabase
verb
I watched my colleagues abasing themselves before the dean:
humble, humiliate, belittle, demean, lower, degrade, disgrace, disparage, debase, cheapen, discredit, mortify, bring low, demote, reduce;
grovel, kowtow, bow and scrape, toady, fawn;
informal crawl, suck up to someone, lick someone's boots.
abase Oxford Dictionary of English