Source : Webster's Revised Unabridged Dictionary (1913)

Cheep \Cheep\, v. i. [imp. & p. p. {Cheeped}.] [Cf. {Chirp}].
   To chirp, as a young bird.

Cheep \Cheep\, v. t.
   To give expression to in a chirping tone.

         Cheep and twitter twenty million loves.  --Tennyson.

Cheep \Cheep\, n.
   A chirp, peep, or squeak, as of a young bird or mouse.

Source : WordNet®

cheep
     n : the short weak cry of a young bird [syn: {peep}]
     v : make high-pitched sounds; of birds [syn: {peep}, {twirp}, {chirp},
          {chirrup}]