The word "fast" refers to something that moves at high speed or occurs in a short amount of time. It can also mean being firmly fixed or secure in place. Additionally, "fast" can describe a period of abstaining from food or drink, particularly in a religious or spiritual context.
The word "fast" originates from Old English "fæst," which means "firm, secure, fixed." It has roots in the Proto-Germanic "fasti" and the Proto-Indo-European "bʰes-" meaning "to be firm, to be strong."