countdown

[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.
Origin
1950-55, Americanism; noun use of verb phrase count down
Examples from the web for countdown
  • Cleared with only seconds left before possibly requiring a scrub, the signal was finally given to continue the countdown.
  • Features an easel display, backlight, and countdown timer.
  • Preferably it should have a large red countdown timer.
  • Game in progress: seven turns left on the countdown clock.
  • It was the physical removal of the tube that led to the perceived inexorability of the countdown.
  • With local elections less than a year away, the countdown has begun.
  • Looking for clarification on new countdown signal requirement.
British Dictionary definitions for countdown

countdown

/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
verb (intransitive, adverb)
2.
to count numbers backwards towards zero, esp in timing such a critical operation
Word Origin and History for countdown
n.

1953, American English, in early use especially of launches of rockets or missiles, from count (v.) + down.