Definition of "pun"

pun¹

/pʌn/

verb
third-person singular simple present puns, present participle punning, simple past and past participle punned
1. (transitive) To beat; strike with force; to ram; to pound, as in a mortar; reduce to powder, to pulverize.
  Quotations
  He would pun thee into shivers with his fist.
  c. 1602, William Shakespeare, “The Tragedie of Troylus and Cressida”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, [Act II, scene i]
2. (intransitive) To make or tell a pun; to make a play on words.
noun
plural puns
1. A joke or type of wordplay in which similar definitions or sounds of two words or phrases, or different definitions of the same word, are deliberately confused.
  Quotations
  "Certainly, my home at my uncle's brought me acquainted with a circle of admirals. Of Rears, and Vices, I saw enough. Now do not be suspecting me of a pun, I entreat."Austen was likely referring to flogging or spanking, then common naval punishments, known as le vice anglais.
  1814 July, [Jane Austen], chapter VI, in Mansfield Park: […], volume I, London: […] T[homas] Egerton, […], page 124

pun²

/pʌn/

noun
plural puns or pun
1. (Korean units of measure) Alternative form of bun: a Korean unit of length equivalent to about 0.3 cm.