Adjective watchful has 2 senses
- argus-eyed, open-eyed, vigilant, wakeful, watchful - carefully observant or attentive; on the lookout for possible danger; "a policy of open-eyed awareness"; "the vigilant eye of the town watch"; "there was a watchful dignity in the room"; "a watchful parent with a toddler in tow"
Antonym: unalert (indirect, via alert)
- insomniac, sleepless, watchful - experiencing or accompanied by sleeplessness; "insomniac old people"; "insomniac nights"; "lay sleepless all night"; "twenty watchful, weary, tedious nights"- Shakespeare
Antonym: asleep (indirect, via awake)
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