off guard

1. Also, off one's guard. Not watchful, easily surprised. It is often put as catch (or be caught) off guard, meaning “take (or be taken) by surprise.” For example, The securities analyst was caught off guard by that financial report, or With any luck the boss will be off guard when I come in late. [Late 1600s] The antonym, on guard or on one's guard, meaning “watchful or prepared, especially to defend oneself,” was first recorded in 1577. For example, In this crowd we must be on guard against pickpockets, or I'm always on my guard when I'm asked how I voted.

Example Sentences

It’s unclear if Guadagnino’s elites believe their moral arguments don’t apply to themselves or if they’re just stupid — or if the script makes them do stupid things to keep the audience off guard.

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The heavy snowfall began on Friday evening, intensifying over the weekend, catching mountain guides off guard.

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But with all of the usual attention on the band as it prepared to release “Silver Bleeds the Black Sun,” there was still one moment that caught everyone off guard.

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On Wednesday, he explained that he had seen a message about "a personal story from my past" on a reporter's phone, which "caught me off guard".

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Miller often called well into the evening, Dudek said, to chastise him about anything the press had reported that day that had caught the administration off guard.

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