Source : Webster's Revised Unabridged Dictionary (1913)

Paronomasia \Par`o*no*ma"si*a\, n. [L., fr. Gr. ?, fr. ? to form
   a word by a slight change; ? beside + ? to name, fr. ? a
   name.] (Rhet.)
   A play upon words; a figure by which the same word is used in
   different senses, or words similar in sound are set in
   opposition to each other, so as to give antithetical force to
   the sentence; punning. --Dryden.

Source : WordNet®

paronomasia
     n : a humorous play on words; "I do it for the pun of it"; "his
         constant punning irritated her" [syn: {pun}, {punning}, {wordplay}]