From Longman Dictionary of Contemporary Englishvigilantvig‧i‧lant /ˈvɪdʒələnt/ adjective WATCHgiving careful attention to what is happening, so that you will notice any danger or illegal activity Please remain vigilant at all times and report anything suspicious. —vigilantly adverbRegisterIn everyday English, people usually use the expression watch out rather than be vigilant:We were told to watch out for anything suspicious.
Examples from the Corpus
vigilant• There had been a rash of petty thefts in the hotel and we were all warned to be vigilant.• The terrorist threat is still real, and the public should remain vigilant.• But Travis McKenna had put paid to that by being particularly vigilant.• We have to be vigilant about protecting our right to privacy.• To combat thieves, it is important for staff to be vigilant at all times.• Travelers in foreign countries are reminded to be vigilant at all times.• We must be ever vigilant. Don't think that Fascism can never rise again. It can.• Abdullahi was a small, slender, restless man with quick, vigilant eyes and an engagingly ugly face.• Be vigilant on public transport and at tourist sites, as pickpockets operate in these areas.• I suspect many parents are vigilant that their children not interrupt others, and surely this is worth attending to.• She had to be particularly vigilant when it came to the large amounts of water threatening them at every turn.remain vigilant• But the National Meningitis Trust says parents must still remain vigilant.• He asked all climbers and walkers to remain vigilant.• We will back the work of the Broadcasting Standards Council and remain vigilant about ensuring high standards in satellite broadcasts from abroad.• Effective change leaders, like those in the Minnesota story remain vigilant against losing sight of performance.• Through such visits the doctor remains vigilant for a change in symptoms.Origin vigilant (1400-1500) Latin present participle of vigilare “to stay awake, keep watch”, from vigil; → VIGIL 