off guard

Idioms  

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.

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Example Sentences

Investors were caught off guard by the yield surge, which suggests that the market had become a little complacent about inflation despite hot consumer and wholesale price readings this week.

From Barron's • May 15, 2026

"The first goal, it's hard for the goalkeeper because the ball goes in front and there are runners so it's hard to see. I think it caught the opposition off guard a bit," Slegers said.

From BBC • Apr. 26, 2026

But the accumulated costs over time can balloon to a sum that can catch budget-conscious seniors off guard.

From MarketWatch • Apr. 15, 2026

Investors were caught off guard by the war, and Fed Chair Jerome Powell indicated officials couldn't ignore the energy supply shock.

From The Wall Street Journal • Mar. 29, 2026

She takes me off guard for a second, and I laugh, surprised by how up-front she is.

From "Five Feet Apart" by Rachael Lippincott