off the cuff (off-the-cuff)
idiom

- not prepared in advance : spontaneous, informal

Merriam-Webster Dictionary

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There are two unconfirmed theories about the origin of the expression "off the cuff." One suggestion is the alleged 1930s practice of speakers writing small notes on the cuffs of their shirts to help them remember what they should say.

The other more popular theory relates to the English pub keepers accounting system, which involved keeping track of the patron's tab by making marks on the starched cuffs of their shirts. This allowed the keeper or bartender to tell at a glance - or off the cuff - how much someone owed for their evening of merriment.

Cuffs are not the only part of our clothing that serve as the basis for idioms and figures of speech. Let's take a look at other parts of our wardrobe:

- knock someone's socks off = to thoroughly surprise someone (The doctor knocked my socks off when he told us we were going to have twins!)

- in someone else's shoes = see or experience something from another person's view (What would you do if you were in my shoes?)

- keep your shirt on! = just wait a minute! (Keep your shirt on! I'll be ready in a few minutes.)

- to be caught with your trousers/pants down = to be asked to do or say something that you are not prepared for (When he asked why I was late for work again, I was caught with my trousers down.)

- tighten one's belt = to spend less money (We have to tighten our belt if we want to make it through the recession)

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SYNONYMS

ad-lib, improvised, impromptu, shot from the hip, played by ear, spontaneous, unscripted

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Practice OWAD in a conversation:

"Audiences appreciate OFF-THE-CUFF speeches because of their spontaneity."