suck–up 
/ˈsʌkˌʌp/ noun
plural suck–ups /ˈsʌkˌʌp/ noun [count] US, informal + disapproving : a person who tries to get the approval of someone in authority by saying and doing helpful and friendly things that are not sincere
▪ I don't think you can give your professor a gift without being considered a suck-up. — see also suck up at 1suck
▪ I don't think you can give your professor a gift without being considered a suck-up. — see also suck up at 1suck
