We found 5 dictionaries that define the word on alert:

General (4 matching dictionaries)

1. on alert: Wiktionary
2. ON ALERT: Dictionary.com

Miscellaneous (1 matching dictionary)

3. ON ALERT: Acronym Finder

Phrases: on the alert, always on alert, more... ▸ Words similar to on alert ▸ Usage examples for on alert ▸ Idioms related to on alert ▸ Wikipedia articles (New!) ▸ Words that often appear near on alert ▸ Rhymes of on alert ▸ Invented words related to on alert