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

Yet while Gap may never be able to reclaim its Y2K heyday, the shares are staging a comeback, up double-digits so far in 2025—although up more modestly since Barron’s recommended them in early December 2024.

From Barron's • Dec. 3, 2025

Young people thrifting clothes as they embrace their Y2K or cottagecore aesthetics have helped secondhand shopping shed its stigma, turning it into a trend, not a necessity.

From MarketWatch • Nov. 19, 2025

Inspired by Liang’s nostalgic memories shopping at Gap in the `90s and 2000s , the collection features low-rise jeans, fuzzy coats and zip-up cropped jackets that look to have leaped out of a Y2K catalog.

From Los Angeles Times • Oct. 31, 2025

But some are copying the Y2K aesthetic in a deliberate nod to the past.

From The Wall Street Journal • Oct. 16, 2025

When the three of them walked out of Pottery Barn, Michael continued, “I mean it. We’ve already got Y2K to worry about, and now this.”

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