definition of
suck up

[1] #1 suck up v. take in, also metaphorically; "The sponge absorbs water well"; "She drew strength from the minister's words". wn

[2] #2 suck up v. ingratiate oneself to; often with insincere behavior; "She is playing up to the chairman". wn

[3] #3 suck up v. try to gain favor by cringing or flattering; "He is always kowtowing to his boss". wn