| a bug that can cause computers or software to misinterpret the first two digits of the year 2000 as 19, due to the coding of dates using only the last two digits of the year. |

| millennium bug n. See Y2K bug. |
| Y2K bug n. A defect in the code of a computer program caused when a year is represented by its last two digits only and the program interprets that year as falling inclusively between 1900 and 1999 instead of between 2000 and 2099. Also called millennium bug. |
millennium bug
Year 2000