millennium bug

American  

noun

Informal.

1. a bug that could cause computers or software to misinterpret a year after 1999 as having the first two digits 19 instead of 20, due to the coding of dates using only the last two digits of the four-digit year.

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millennium bug British  

noun

1. computing any software problem arising from the change in date at the start of the 21st century

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Etymology

Origin of millennium bug

First recorded in 1990–95

Example Sentences

Y2K, aka the Millennium Bug or the Year 2000 Problem, refers to a worldwide panic that occurred on-world as the calendar neared January 1, 2000.

From Literature

Twenty five years ago computer programmers were racing to fix the millennium bug amidst fears that it would cause banking systems to crash and planes to fall out of the sky.

From BBC

While the impact of the millennium bug might have been minimal in the first days of 2000, that's because an immense amount of work had gone into fixing it ahead of a known deadline, says François Dupressoir, associate professor in cryptography at the University of Bristol.

From BBC

It is often tempting to look upon Vladimir Putin as the millennium bug in a human and deadly form.

From BBC

To them, as they navigate world-threatening issues such as climate change and the coronavirus, the idea of the millennium bug seems quaint.

From New York Times