from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A wire stretched near ground level to trip or ensnare an enemy.
- n. A wire or line that activates a weapon, trap, or camera, for example, when pulled.
- n. A small military force whose involvement in hostilities will trigger the use of a larger force.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A cord or wire arranged so that when snagged or pulled by an intruder, it will trigger a detector or trap or a device, such as a land mine.
- n. Any means of detecting intruders.
trip + wire (Wiktionary)