adjective

alert

uh-LURT/ʌlˈɝt/

Attentive and ready to respond.

The alert goalkeeper watches the approaching ball with ready hands.

A goalkeeper watches an approaching soccer ball intently, balanced on bent knees with open gloved hands ready to intercept it.

Etymology

aItalianto

+lItalianthe

+ertItalianlookout; high tower

The phrase “to the height” referred to a lookout or high tower and acquired the sense “on the watch.” That watchfulness became the modern quality of attentive readiness.

In context

Lucca4:11

but tonight you'd make Sleeping Beauty look alert

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More examples

She remained alert during the night watch.
He was alert to small changes in the sound.
The dog became more alert at the noise.

Forms

alert

alertness noun — Attentive readiness.

Similar words

attentive: Pays close attention.
vigilant: Keeps careful watch for danger or trouble.