Definition of the word flash on

The term "flash on" originated in the context of photography and refers to the moment when a flash unit is activated and emits a short burst of light. The term can be traced back to the early days of flash photography, when portable flash units were first introduced in the mid-20th century. Before the development of portable flash units, photographers had to rely on available light or expensive, bulky studio equipment to illuminate their subjects. Portable flash units, which used small batteries to power a xenon or halogen bulb, revolutionized the industry, allowing photographers to shoot in low-light conditions or in situations where the available light was not sufficient. The phrase "flash on" comes from the sound that the unit makes when it is activated. The term has since been adapted and used more broadly to refer to any sudden or abrupt event that is accompanied by a flash, such as a lightning strike or the activation of a car's headlights in an oncoming car's headlights as it approaches. Overall, the term "flash on" continues to be an important part of the lexicon of photographers and visual artists, as well as a common idiom in everyday language to describe sudden, bright, or intense events.