a very short time (as the time it takes the eye to blink or the heart to beat)
"if I had the chance I'd do it in a flash"
A very short, unspecified length of time.
Alternative form of Jiffy bag.
The origin of "jiffy" is unknown, though it may have started as thieves' slang for "lightning." The word was also formerly spelled "giffy," possibly linked to the term "gliff."