head off

British  

verb

1. to intercept and force to change direction

   to head off the stampede

2. to prevent or forestall (something that is likely to happen)

3. to depart or set out

   to head off to school

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head off Idioms  

1. Block the progress or completion of; also, intercept. For example, They worked round the clock to head off the flu epidemic, or Try to head him off before he gets home. [First half of 1800s] This expression gave rise to head someone off at the pass, which in Western films meant “to block someone at a mountain pass.” It then became a general colloquialism for intercepting someone, as in Jim is going to the boss's office—let's head him off at the pass.

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Example Sentences

New medical guidelines aim to head off damage early with lifestyle changes, screening tests and medication.

From The Wall Street Journal • Mar. 31, 2026

Samar shares the popular view that for every senior official "they've reportedly assigned three to seven successors. Like a hydra - you cut one head off, another grows back. They won't surrender any time soon."

From BBC • Mar. 25, 2026

Only 39, he took up the role with gusto, launching into an anti-crime drive that proved popular with the electorate but not enough to keep his head off the chopping block.

From Barron's • Feb. 17, 2026

Officials from the U.S. and Iran held a first round of talks last week, and Trump has indicated that he is open to making a deal with Tehran to head off military action.

From The Wall Street Journal • Feb. 13, 2026

And could the United States glean enough intelligence from its $20 million device to head off its Soviet adversary and avert a nuclear war?

From "Spies: The Secret Showdown Between America and Russia" by Marc Favreau