word play

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun Used other than as an idiom: see word,‎ play.
• noun A technique in which the nature of the words used become part of the subject of the work, such as puns, phonetic mix-ups such as spoonerisms, obscure words and meanings, clever rhetorical excursions, oddly formed sentences, and telling character names.