Synonyms for Suck Up (same or very similar meaning)
WordNet sense 1 (ingratiate oneself to; often with insincere behavior):
cozy up, cotton up, play up, shine up, sidle upWordNet sense 2 (take in, also metaphorically):
absorb, draw, imbibe, suck, take up, take in, sop up, soak upWordNet sense 3 (try to gain favor by cringing or flattering):
fawn, kowtow, toady, truckle, bootlick, kotowFrom the ODE community, based on WordNetadd/edit