See truckle in Webster's New World Roget's A-Z Thesaurus II
verb
To support slavishly every opinion or suggestion of a superior:
bootlick, cringe, fawn, grovel, kowtow, slaver, toady. (Informal) apple-polish, brownnose, cotton. (Slang) suck up. Idioms: curry favor, dance attendance, kiss someone's feet, lick someone's boots. See over
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