To head off

to intercept; to get before; as, an officer heads off a thief who is escaping.

See also: Head

References in classic literature ?
Lady Greystoke had been sitting a little way from the cabin, and when she heard his cry she looked up to see the ape springing with almost incredible swiftness, for so large and awkward an animal, in an effort to head off Clayton.
After reversing into the "down loop" line at Eaglescliffe at around 10.43am, it is then due to head off again at 11.16am, steaming over Yarm viaduct on its way to York, where it's scheduled to arrive at 12.14am.
Summary: Beijing: Japan scrambled fighter jets Thursday to head off a number of Chinese military planes ...
THE Government will today announce a string of concessions over controversial welfare reforms to head off a damaging Lib Dem rebellion.
TRIPOLI, Lebanon: Sunday's rally was marred by the death of a teenager in a road accident in Akkar, which required a heavy army deployment to head off sectarian tension.
Summary: Newlyweds William and Kate are expected to head off to a mystery honeymoon location on Saturday.
It's also a good idea to go ahead and replace all those old external valves now to head off problems later.
Facing an official Star Fleet Inquiry in connection with some of his command decisions that were not totally in line with established Starfleet procedures, Picard chooses to head off in pursuit of an alien being who has achieved super powers from exposure to the radiation of the galactic barrier.
One common problem, the authors say, is that "people tend to hold positive illusions that lead us to interpret events in an egocentric manner and to undervalue risks." Moreover, managers are usually reluctant to invest to prevent vague and distant problems, and tend to preserve the status quo instead of accepting the large-scale change that may be needed to head off looming troubles.
To head off such reactions, the NTP's new Report on Carcinogens points out that many of the listed carcinogens, including some drugs, offer society substantial benefits and urges people not to eschew such agents without consulting a doctor or other expert.
Companies could be planning to introduce "love contracts" to head off any problems caused by staff striking up relationships at work, the TUC has claimed.