Search Result for "red alert":
Wordnet 3.0

NOUN (1)

1. the highest level of alert when an attack by the enemy seems imminent (or more generally a state of alert resulting from imminent danger); 



WordNet (r) 3.0 (2006):

red alert
    n 1: the highest level of alert when an attack by the enemy
         seems imminent (or more generally a state of alert
         resulting from imminent danger)