In everyday language, a jiffy usually refers to a short period of time.
If someone says that he will be back in a jiffy, the person usually means that he will be back shortly.
In physics, Gilbert Newton defined a jiffy as the time it takes light to travel a distance of 1 centimeter.
According to Gilbert Newton, that time is 33.3564 microseconds or
33.3564 × 10-12 seconds .
In computer engineering, a jiffy could vary from 10 milliseconds to 1/50 second.
In electrical engineering, 1/50 or 1/60 is the time it takes alternating current to complete 1 cycle.