What is jiffy? - Definition from WhatIs.com
Part of the Computing fundamentals glossary:

The term jiffy refers to a brief, usually unspecified, interval of time . In scientific and lay applications, it can refer to any of several specific time spans. The most common interpretation is 0.01 second.

In computer engineering, the length of time between successive microprocessor clock cycle s is sometimes called a jiffy. This interval gets shorter as clock speeds increase. In a computer with a 2- gigahertz microprocessor, the jiffy is 0.5 nanosecond or 5 x 10 -10 second. In a machine with a 3-gigahertz microprocessor, the jiffy is 0.333 nanosecond (3.33 x 10 -10 second).

In some circles, the length of time required for one alternating-current ( AC ) utility power cycle is called a jiffy. In the United States and Canada, this is 1/60 second. In many other countries, it is 1/50 second.

In some publications, the term jiffy refers to 0.001 second. In others, it corresponds to the length of time required for a beam of light to travel one foot in free space; this is approximately 1 nanosecond. In still others, it refers to 3.3357 times 10 -11 seconds, which is the length of time it takes a ray of light to travel 1 centimeter in free space. Perhaps the most interesting interpretation is the one suggested by Richard Tolman early in the 20th century. He considered a jiffy to be the length of time it takes a photon (light particle) to travel from one side of a nucleon (neutron or proton) to the other. A nucleon has a diameter of about 10 -15 meter; a jiffy in this context is a paltry 3.3357 x 10 -24 second.

The origin of the term jiffy is unknown. It is thought to have first been used in England during the 1700s, and referred to a brief but indeterminate time. But in some contexts, it is used as a put-off: the expression in a jiffy can mean "maybe now, maybe never."

This was last updated in September 2005
Posted by: Margaret Rouse

Related Terms


  • photonics

    - Photonics is an area of study that involves the use of radiant energy (such as light), whose fundamental element is the photon. (WhatIs.com)

  • laser

    - A laser is a coherent and focused beam of photons; coherent, in this context, means that it is all one wavelength, unlike ordinary light which showers on us in many wavelengths. The acronym laser s... (WhatIs.com)

  • cyberextortion

    - Cyberextortion is a crime involving an attack or threat of attack against an enterprise, coupled with a demand for money to avert or stop the attack. (SearchSecurity.com)


  • Computing fundamentals

    - Terms related to computer fundamentals, including computer hardware definitions and words and phrases about software, operating systems, peripherals and troubleshooting.

  • Internet applications

    - This WhatIs.com glossary contains terms related to Internet applications, including definitions about Software as a Service (SaaS) delivery models and words and phrases about web sites, e-commerce ...

Ask a Question About jiffyPowered by ITKnowledgeExchange.com

Get answers from your peers on your most technical challenges

Tech TalkComment



    Contribute to the conversation

    All fields are required. Comments will appear at the bottom of the article.