Definitions

1. noun

a series of numbers or a period of time counting down to a particular date, event, or moment

“The TV show started its final countdown to the New Year.”

2. verb

to count down from a certain number or time, typically in a public or formal manner

“The astronauts began to countdown to the launch of the spaceship.”

3. noun

a period of time counted down, especially the last part of it

“The final countdown to the deadline was intense.”