A jiffy is a much more specific period of time than we think. The term comes from astrophysics and quantum physics and was coined by Edward R. Harrison. It is equal to roughly 1/100th of a second. As there are exactly 3600 seconds in an hour and 86,400 seconds in a day, we experience 8,640,000 jiffies every day. Also, due to the amount of time in a jiffy being so small, it is physically impossible to “be back in a jiffy”, unless you are planning on not going anywhere at all.