split second

American  

noun

1. a fraction of a second.

2. an infinitesimal amount of time; instant; twinkling.

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split second British  

noun

1. an extremely small period of time; instant

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adjective

1. made or arrived at in an infinitely short time

   a split-second decision

2. depending upon minute precision

   split-second timing

split second Idioms  

1. An instant, a fraction of a second, as in Our best swimmer came in a split second before theirs. This expression alludes to a stop watch that has two second hands, one above the other, for timing more than one athlete or intervals of a race by a single athlete. Each hand can be stopped independently of the other, so a second can be “split” when one second hand stops a fraction of a second after the other. [c. 1880]

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Other Word Forms

• split-second adjective

Etymology

Origin of split second

First recorded in 1880–85

Example Sentences

In that "split second", he must have realised Harry might be killed or injured, but Mr Justice Cavanagh said: "In the moment, you did not care if he lived or died."

From BBC

The majority use one of two styles to achieve this, often in split seconds - pushing, or grappling.

From BBC

A split second after “Action!” was called, I darted across the hall to a better spot and ran through the frame.

From The Wall Street Journal

To be aware of, 'I'm on the ball here so this is what we trained' - but you have to think that in a split second.

From BBC

The lawyer who represented his family at his inquest, Gareth Naylor, tells the BBC that in a "split second" of an adult leaving the room, the toddler climbed on a bed and fell.

From BBC

Related Words

• blink of an eye
• millisecond
• nanosecond