A play on words
Definition 1 of 1
Pro Tip 1/3Cultural Wit
Understand that play on words often involves cultural references which may not translate well across different languages. 
The phrase 'time flies like an arrow; fruit flies like a banana' plays on the word 'flies'.
Pro Tip 2/3Humorous Effect
A play on words is mainly used for humor or to attract interest by being clever. 
He said he was a 'stand-up' guy, meaning he's honest, but he was sitting down.
Pro Tip 3/3Context Is Key
The context of the conversation determines how a play on words is interpreted. 
At the bakery, 'doughnut' worry was a playful pun intended to ease stress.