"vigilance" in the noun sense
1. watchfulness, wakefulness, vigilance, alertness
the process of paying close and continuous attention
"wakefulness, watchfulness, and bellicosity make a good hunter"
"vigilance is especially susceptible to fatigue"
2. watchfulness, vigilance, weather eye
"he keeps a weather eye open for trouble"
Source: WordNet® (An amazing lexical database of English)
Princeton University "About WordNet®."
WordNet®. Princeton University. 2010.
View WordNet® License