A double entendre is a figure of speech or a particular way of wording that is devised to have a double meaning, one of which is typically obvious, and the other often conveys a message that would be too socially unacceptable, or offensive to state directly.
Lodgings to Let, an 1814 engraving featuring a double entendre. He: "My sweet honey, I hope you are to be let with the Lodgins!" She: "No, sir, I am to be let alone".
The first page of the poem "The Wanderer" found in the Exeter Book.
Flax on a distaff
In The Office, Michael Scott (played by Steve Carell, pictured) often points out unintentional double entendres with the phrase "that's what she said"
A pun, also rarely known as paronomasia, is a form of word play that exploits multiple meanings of a term, or of similar-sounding words, for an intended humorous or rhetorical effect. These ambiguities can arise from the intentional use of homophonic, homographic, metonymic, or figurative language. A pun differs from a malapropism in that a malapropism is an incorrect variation on a correct expression, while a pun involves expressions with multiple interpretations. Puns may be regarded as in-jokes or idiomatic constructions, especially as their usage and meaning are usually specific to a particular language or its culture.
A black Jeep Wrangler with license plate BAABAAA – a pun on "Baa, Baa, Black Sheep"
The Tiecoon Tie shop, in Penn Station NY, an example of a pun in a shop name