Pune
A pune or a play on words is often spoken by Discworld characters when they tell a not very funny joke based on word play.
One particular pune that appears a lot on the Discworld is A leopard can't change his shorts.
Named after the founder of the Fools Guild, one Jean-Paul Pune who, in his magnum opus, Essay on a form of wit devotes 160,000 words to defining the Five Great Classes and seventy-three sub-classes of the Pune or play on words, which all students at the Fools' Guild are expected to commit to memory on pain of pain. The sacred and time-honoured art is currently taught at the Guild School by Cloistered Clown Brother Frere.
It is known that the Patrician's artistic sensibilities can be irritated by excessive or particularly egregious use of the Pune or play-on-words, which, if the Mail Order business is anything to go by, he places in the same category of offense as mime artistry or abstract modern art.
Annotation
The very name Pune is a pun, or play on words, on the Roundworld word pun.
There is a professional cricket team in the Indian Premier League called the Pune Warriors. Terry Pratchett would approve.