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Welcome to English in A Minute. A cuff is the part of a shirt that ends at your wrist. Here is the idiom that uses this word: off the cuff. What could that mean? Let's find out.
---I have to give a speech tomorrow and I really do not have time to write it. I will put together some notes. But I think it would be mostly off the cuff.
---That should not be a problem. You do really well when you do not have a script. I think you are best speeches are usually off the cuff.
---Really?
This idiom means to speak without much planning. It comes from long ago when many men wore cuff made of paper which they could write on. This let them speak by reading the notes off the cuff. That's English in a minute.