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

In the film, Rogan reads from Swan’s book, Countdown, that “the modern world is threatening sperm counts and is imperiling the future of the human race.”

From Slate • Apr. 16, 2026

The celebrity, who has previously said she has a home in Pembrokeshire and in Bristol, made her name as the maths expert on Channel 4's Countdown.

From BBC • Mar. 13, 2026

More than 100 of Nexstar Media Group’s local television stations will air “Coast-to-Coast Countdown 2026,” a live special featuring music, special guests, fireworks and a drone show.

From Los Angeles Times • Dec. 29, 2025

On Dec. 31, attention shifts to Julefest’s Copenhagen Countdown in Solvang Park, ringing in the Danish new year at 3 p.m.,

From Los Angeles Times • Sep. 9, 2025

“We’ll practice it a little today. We’ll also tighten up ‘The Final Countdown.’

From "Auggie & Me" by R. J. Palacio