(1):

(v. t.) To inform against; hence, to calumniate.

(2):

(v. t.) To play the sycophant toward; to flatter obsequiously.

(3):

(n.) An informer; a talebearer.

(4):

(n.) A base parasite; a mean or servile flatterer; especially, a flatterer of princes and great men.

(5):

(v. i.) To play the sycophant.