from The American Heritage® Dictionary of the English Language, 4th Edition
- n. The counting backward aloud from an arbitrary starting number to indicate the time remaining before an event or operation, such as the launching of a missile or space vehicle.
- n. The checks and preparations carried out during this activity.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A count backward in fixed units to the time of some event, especially the launch of a space vehicle
- n. The acts of preparation carried out during this period
- n. A radio or television program counting down the top songs of a given week, usually in reverse order ending with the No. 1.
- v. To count down
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. counting backward from an arbitrary number to indicate the time remaining before some event (such as launching a space vehicle)
count + down (Wiktionary)