PIN number (plural PIN numbers)
- A common alternative form of PIN (in the sense of "personal identification number").
- "PIN number" is a pleonasm as the "N" of "PIN" stands for "number".
- The use of "PIN number" rather than "PIN" is widespread but is avoided by careful speakers and writers.
- Some people may argue that "PIN number" is not redundant, as it avoids confusion with the word pin.