Jiffy

A jiffy is a very short amount of time. It is also, unusually for a figure of speech, a real unit. In physics one jiffy is the time it takes light to travel one centimetre, which is about 33 trillionths of a second. Anyone who has promised to be back “in a jiffy” has therefore been late every single time.^[1]

Definitions

The jiffy has several official lengths, depending on who is asked, and every one of them is short.

• Physics: the time light takes to cross one centimetre, about 33.4 picoseconds. Suggested by the American chemist Gilbert N. Lewis.
• Electronics: one cycle of the mains electricity supply, 1/50 or 1/60 of a second depending on the country.
• Computing: one tick of a computer's system timer, which varies from machine to machine.
• Kitchens: about ten minutes.

Measurement

The phrase “in a jiffy” has been in use since the late 18th century, and nobody knows where the word came from. Etymologists tried to look into it quickly, and are still at it.^[2]

The jiffy is one of several units of time that sound made up but are not. Nuclear physicists use the shake, ten billionths of a second, named after a shake of a lamb's tail. Proposals for a tick, a tick-tock and a hang on are still with the committee, which says it will get to them in a minute.^[3]

See also

• Second – about 30 billion jiffies
• Minute – what a jiffy turns into in the kitchen
• Time
• Hiccup – how long one lasts

References

1. Quick, Q. (1998). Back in a Jiffy. Light Press. Not back.
2. Origins Bureau (1903–present). “Jiffy: Interim Report”. Ongoing.
3. Committee on Short Units (2011). Pending Units. To follow shortly.