Used attributively ("flash sale", "flash flood") and as informal British adjective meaning "showy".
Definitionen
Informal, chiefly British: showy or ostentatious; stylish in a way that is intended to attract attention. He turned up in a flash suit that cost a fortune.
Happening suddenly and lasting for only a short time; occurring rapidly. They made a flash decision that saved the company.
Computing: involving or using flash memory technology. Flash storage devices are common in modern laptops.
Used alone to announce urgent news or imitate a sudden burst of light/action.
Definitionen
Used to signal breaking news or to represent a sudden burst of light or action. "Flash! The president has announced a surprise visit," the reporter exclaimed.