Your instructor may say something like “Look out for the hazard around the corner”.
A hazard is something usually in the road that may cause you to slow down or change direction. If you don’t deal with the hazard in good time, it can develop into something serious or dangerous.
Sometimes the hazard is already dangerous, like an accident in the road and other times it could just be a parked car on a bend or a cyclist ahead.
To increase learner’s understandings of hazards in general, the DVSA introduced the ‘hazard perception test’ in November 2002 which is now part of the theory test.