Y2K

American  

[wahy-too-key] / ˈwaɪˌtuˈkeɪ /

abbreviation

1. the year 2000.

2. Also called Y2K bug.  Also called millennium bug.  Also called Y2K problem,.  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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adjective

1. relating to or characteristic of the late 1990s and early 2000s.

   The outfit merges Y2K aesthetics with contemporary trends.

Y2K British  

noun

1. another name for the year 2000 _ad (esp referring to the millennium bug)

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Etymology

Origin of Y2K

First recorded in 1995–2000; Y(ear) + 2 + K symbol for the number 1000

Example Sentences

See Examples For:

Y2K

The costume, a denim vest and pants set with extremely Y2K lace-up details, is representative of the show’s approach to fashion trends.

From Los Angeles Times ● Jun. 30, 2026

So-called Y2K fashion has already caught on with members of Generation Z. Now, some of the hottest stock-market names from that era are also being embraced by a new cohort of investors.

From MarketWatch ● May 15, 2026

In the first two decades since Y2K, by contrast, deaths have averaged around three per term.

From Slate ● Apr. 24, 2026

The Y2K warnings were dire, but the technological fixes largely worked.

From The Wall Street Journal ● Apr. 14, 2026

Who would take care of Mr. Mosley when Y2K hit?

From "The First State of Being" by Erin Entrada Kelly