Noun--A self-seeking, servile flatterer and a fawning parasite.
toady, yes man, flunky, fawner, flatterer.
1)My friend is a big sycophant and always tries to flat lecturers to acquire marks.
2)A chief minister of a state should be very commanding but not a sycophant to any.
3)Peter is very toady and flattered his friend and now he is considered as a sycophant among relatives..