sycophant vs ass-kisser

sycophant and ass-kisser both are nouns.

Word	Noun	Adjective	Verb	Adverb
sycophant	Yes	No	No	No
ass-kisser	Yes	No	No	No

As nouns, sycophant and ass-kisser are synonyms defined as:

sycophant and ass-kisser: a person who tries to please someone in order to gain a personal advantage

Other synonyms of sycophant include crawler, lackey, toady.

sycophant (noun)	ass-kisser (noun)
a person who tries to please someone in order to gain a personal advantage	a person who tries to please someone in order to gain a personal advantage