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

She screamed her head off as a baby.

From Literature

Instead, you’re heading off to the Tar Heel State to spend your days hunting... coyotes.

From Los Angeles Times

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

Then one evening the dog’s owner was there with him at the gate, the dog barking his head off as usual.

From Literature