auffahren

Auffahren is a German verb with the prefix auf- attached to fahren. It describes movement related to driving or riding toward a location and has several closely related senses depending on context.

In everyday traffic usage, auffahren most commonly means to drive up to or into something, especially to collide with another vehicle or object. In this sense, it is used to describe rear-end or secondary collisions, as in a car that "fährt auf" the vehicle in front. The phrase is frequently found in accident reports and news coverage, for example: "Der Fahrer fuhr auf den Wagen vor ihm auf." The action can be transitive or intransitive, and the past tense forms vary between simple and perfect constructions (e.g., "er fuhr auf" or "er ist aufgefahren").

A second, more neutral sense covers approaching or driving up to a location, such as a platform, ramp, driveway, or loading area. In railway, road, or harbour contexts, a vehicle or train can "auf[ge]fahren" to a designated point, meaning it arrives at or reaches that point. For example: "Der Zug fährt auf Gleis 1 auf" or "das Auto fährt die Auffahrt zur Garage hinauf." This use emphasizes the movement toward a specified place rather than a collision.

Grammatically, auffahren is a separable prefix verb. In main clauses, the prefix normally separates and appears as auff in the finite verb form (er fährt auf, sie fährt auf). In perfect tenses with the intransitive sense of movement, the auxiliary is typically sein (er ist aufgefahren).

See also: Auffahrunfall, the term for a rear-end collision.