Source : Webster's Revised Unabridged Dictionary (1913)

Cherup \Cher"up\, v. i. [Prob. fr. chirp.]
   To make a short, shrill, cheerful sound; to chirp. See
   {Chirrup}. ``Cheruping birds.'' --Drayton.

Cherup \Cher"up\, v. t.
   To excite or urge on by making a short, shrill, cheerful
   sound; to cherup to. See {Chirrup}.

         He cherups brisk ear-erecting steed.     --Cowper.

Cherup \Cher"up\, n.
   A short, sharp, cheerful noise; a chirp; a chirrup; as, the
   cherup of a cricket.