What does a blowout refer to in well control terminology?

A blowout in well control terminology specifically refers to an uncontrolled kick that exits at the surface, resulting in the uncontrolled release of oil, gas, or formation fluids from the well. This typically occurs when there is a failure in a well's pressure control system, allowing hydrocarbons to rise to the surface without being contained.

The context of well control emphasizes maintaining control over well pressures to prevent such catastrophic events, making the understanding of a blowout critical for proper safety measures and response strategies. It underscores the importance of monitoring and managing downhole pressures to prevent the escalation of kicks, which, if not controlled, can lead to a blowout, posing safety hazards and environmental risks.

In contrast, the other options describe scenarios that do not reflect the uncontrolled nature of a blowout. Controlled fluid flow indicates successful management of pressure without any uncontrolled release, while incremental pressure increase and reduction of fluid pressure suggest situations that are part of the well management process but do not specifically indicate a blowout condition.