reignition

Reignition is the act of igniting something again after a flame or ignition source has been extinguished. The term combines the prefix re-, meaning again, with ignition, which derives from the Latin ignis for fire. It is used across technical and nontechnical contexts to describe restarting combustion or a flame after a pause, shutdown, or misfire.

In engineering, reignition refers to restarting a flame within a combustion chamber after it has been extinguished. In spark-ignition engines, reignition is achieved by triggering the spark plug to restart combustion. In compression-ignition engines and gas turbines, reignition may involve a pilot flame, dedicated igniters, or specific fuel-air conditions to reestablish stable combustion. Reignition is important to prevent power loss, reduce downtime, and manage safety during shutdown procedures.

In propulsion and aerospace, re-ignition denotes restarting a rocket or jet engine after a previous burn. Re-ignitable engines are designed to tolerate restart transients, manage propellant conditioning, and control pressure and timing for continued operation. Reignition capability is a key feature in upper-stage maneuvers and missions requiring multiple engine burns.

Outside technical uses, reignition can describe the revival of a flame in a laboratory reaction or, more broadly, the renewed interest or activity in a project, movement, or interest after a period of dormancy.

See also: ignition, ignition system, engine restart, rocket engine restart, misfire.