countdown

American  

[kount-doun] / ˈkaʊntˌdaʊn /

noun

1. the backward counting in fixed time units from the initiation of a project, as a rocket launching, with the moment of firing designated as zero.

2. the final preparations made during this period.

3. a period of increasing activity, tension, or anxiety, as before a deadline.

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countdown British  

/ ˈkaʊntˌdaʊn /

noun

1. the act of counting backwards to time a critical operation exactly, such as the launching of a rocket or the detonation of explosives

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verb

1. to count numbers backwards towards zero, esp in timing such a critical operation

Etymology

Origin of countdown

1950–55, noun use of verb phrase count down

Explanation

When you list a sequence of numbers in reverse order, ending in zero, that's a countdown. When you're preparing to launch your model rocket, you can make it more exciting with a countdown! "Five, four, three, two, one, blast off!" is a countdown that may sound familiar if you've ever watched footage of a NASA space shuttle launch. You might also hear a countdown on New Year's Eve, as revelers count down the seconds until midnight and the beginning of a new year. This word comes from American English, first appearing in the 1950s in the context of rocket launches.

Example Sentences

Despite the promising developments on Friday, the countdown clock for world food prices is very much ticking.

From BBC • Apr. 18, 2026

He clearly realized, as the countdown clock clicked on, that he had overstepped and was eager, even desperate, for an off-ramp.

From Slate • Apr. 8, 2026

"Financial markets are oscillating in a narrow, uneasy range as traders sized up the countdown to Donald Trump's Iran deadline," wrote Stephen Innes at SPI Asset Management.

From Barron's • Apr. 7, 2026

Thankfully, the countdown can now be measured in hours and minutes rather than months, with the 98th Academy Awards slated to start Sunday at 4 p.m. at the Dolby Theatre at Ovation Hollywood.

From Los Angeles Times • Mar. 15, 2026

The countdown kept stopping as technicians made final checks.

From "Fallout: Spies, Superbombs, and the Ultimate Cold War Showdown" by Steve Sheinkin