off-guard

Definitions

Unprepared for a sudden or unexpected event.

In a state of being vulnerable or not alert.

Examples

The sudden question caught him completely off-guard, and he struggled to find an answer.

She kept her opponent off-guard by constantly changing her strategy throughout the match.

Synonyms

unprepared unaware caught napping taken by surprise inattentive unready unguarded

Antonyms

prepared alert vigilant ready watchful attentive on one's toes