( informal , disapproving ) to try to please sb in authority by praising them too much, helping them, etc., in order to gain some advantage for yourself
SUCK UP (TO SB)
Meaning of SUCK UP (TO SB) in English
Oxford Advanced Learner's English Dictionary. Оксфордский английский словарь для изучающик язык на продвинутом уровне. 2005