1. phrasal verb If you head off a person, animal, or vehicle, you move to a place in front of them in order to capture them or make them change the direction they are moving in. [V n P] ⇒ He changed direction swiftly, turned into the hallway and headed her off. [Also V P n] 2. phrasal verb → head If you head something off, especially something unpleasant, you take action before it is expected to happen in order to prevent it from happening. [V P n] ⇒ He would ask Congress to intervene and head off a strike. [V n P] ⇒ You have to be good at spotting trouble on the way and heading it off.
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