unsleeping, awake, restless, restive, tossing and turning, without sleep, wide awake, insomniac;
archaic watchful.
▷antonyms sleeping, asleep.
2 I was suddenly wakeful:
alert, on the alert, vigilant, hypervigilant, on the lookout, on one's guard, on one's toes, on the qui vive, watchful, observant, attentive, sharp, heedful, wary.
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