Synonyms of watchful

Adjective

1. alert (vs. unalert), watchful, argus-eyed, open-eyed, vigilant, wakeful, fly, heads-up, wide-awake, lidless, sleepless, awake, lively, wary

usage: engaged in or accustomed to close observation; "caught by a couple of alert cops"; "alert enough to spot the opportunity when it came"; "constantly alert and vigilant, like a sentinel on duty"

2. insomniac, sleepless, watchful, awake(predicate) (vs. asleep)

usage: experiencing or accompanied by sleeplessness; "insomniac old people"; "insomniac nights"; "lay sleepless all night"; "twenty watchful, weary, tedious nights"- Shakespeare

Definition and meaning of watchful (Dictionary)