vigilanta GRE synonym for 'alert' meaning staying continuously on guard, watching closely for any sign of danger without ever letting one's attention lapseBorder agents must remain vigilant during every shift to prevent illegal crossings.NoteBorder agents must remain vigilant during every shift to prevent illegal crossings.Elon.io is an online learning platformWe have an entire course teaching GRE Verbal — Essential Vocabulary grammar and vocabulary.Start learning GRE Verbal — Essential Vocabulary now