Ausfall

Ausfall is a German noun with several related meanings: outage, failure, cancellation, and absence. It is used in many contexts to denote that something is not functioning, not available, or has been omitted. The verb ausfallen means “to fall out,” “to be cancelled,” or “to fail.”

Etymologically, ausfall comes from aus- (out) and fallen (to fall). In technical language it describes an interruption of service or a device that stops operating. In everyday speech, it can also refer to the absence of a person or an event.

In technology and infrastructure, Ausfall is commonly used in compounds such as Stromausfall (power outage), Systemausfall or Serverausfall (system or server failure), Dienstausfall (service interruption), and Netzausfall (network outage). The term denotes a period of unavailability or reduced functionality.

In operations and events, Ausfall can indicate the cancellation of an appointment or class, or the absence of participants. It is also used to describe staff shortages, for example personeller Ausfall due to illness.

Related terms include Unterbrechung, Störung, Panne, and Auszeit; the opposite concept is Verfügbarkeit or Funktionsfähigkeit. Downtime can be referred to as Ausfallzeit, and the likelihood of an outage is sometimes described as Ausfallrisiko.