Synonyms of the word

watchful

• adj. observant, vigilant and aware.

alert

• adj. Attentive; awake; on guard.
• adj. (obsolete) Brisk; nimble; moving with celerity.
• n. An alarm.
• n. A notification of higher importance than an advisory.
• v. To give warning to.

argus-eyed

• adj. ever vigilant.

awake

• adj. Not asleep; conscious.
• adj. (by extension) Alert, aware.
• v. (intransitive) To become conscious after having slept.
• v. (transitive) To cause (somebody) to stop sleeping.
• v. (transitive) to excite or to stir up something latent.
• v. (transitive, figuratively) To rouse from a state of inaction or dormancy.
• v. (intransitive, figuratively) To come out of a state of inaction or dormancy.

insomniac

• n. One who suffers an inability or difficulty sleeping; a sufferer from insomnia.
• adj. Suffering from or pertaining to insomnia.

open-eyed

• adj. alert and vigilant.

sleepless

• adj. Characterized by an absence of sleep.

vigilant

• adj. Watchful, especially for danger or disorder; alert; wary.

wakeful

• adj. Awake; not sleeping.
• adj. Sleepless.
• adj. Vigilant and alert; watchful.