Synonyms

off guard

Idioms

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

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

These costs have been catching employers off guard, especially with the increased use of agentic AI sucking up tokens.

From MarketWatch • Jun. 4, 2026

He used his fastball to get to two strikes, too, catching Marsh off guard with, as Wrobleski put it, “a modified, slide-step, out-of-the-windup fastball” off the plate.

From Los Angeles Times • May 30, 2026

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 nature of the camera in Meta's glasses can be so unobtrusive that even their wearers have been caught off guard by what and when they're recording, and where those recordings are going.

From BBC • May 13, 2026

Danny is bewildered, caught completely off guard when he’s touched.

From "Black Brother, Black Brother" by Jewell Parker Rhodes

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023