wɒtʃ
wɑːtʃ
1 [countable] a type of small clock that you wear on your wrist, or (in the past) carried in your pocketShe kept looking anxiously at her watch.My watch is fast/slow.2 [singular, uncountable] the act of watching somebody/something carefully in case of possible danger or problemsThe police have mounted a watch outside the hotel.I'll keep watch while you go through his papers (= watch and warn you if somebody is coming).The government is keeping a close watch on how the situation develops. see also neighbourhood watch3 [countable, uncountable] a fixed period of time, usually while other people are asleep, during which somebody watches for any danger so that they can warn others, for example on a ship; the person or people who do thisI'm on first watch.I go on watch in an hour. see also nightwatchmanIdioms
be on the watch (for somebody/something)
to be looking carefully for somebody/something that you expect to see, especially in order to avoid possible danger
Be on the watch for thieves.