Source : Webster's Revised Unabridged Dictionary (1913)

Kitten \Kit"ten\, n. [OE. kiton, a dim. of cat; cf. G. kitze a
   young cat, also a female cat, and F. chaton, dim. of chat
   cat, also E. kitling. See {Cat}.]
   A young cat.

Kitten \Kit"ten\, v. t. & i. [imp. & p. p. {Kittened}; p. pr. &
   vb. n. {Kittening}.]
   To bring forth young, as a cat; to bring forth, as kittens.
   --Shak. H. Spencer.

Source : WordNet®

kitten
     n : young domestic cat [syn: {kitty}]

kitten
     v : have kittens; "our cat kittened again this year"