split-second

plural split-seconds · alternative split second

1. attributiveA stopwatch with two second hands, each of which may be stopped separately to time the intervals of a race by a sportsperson, or to time more than one sportsperson.
2. A fraction of a second; hence (figurative, also attributive) a very short time period; an instant, a moment.

   It's very dangerous, though, when a man thinks for a split second that he understands death.

   1912, G[ilbert] K[eith] Chesterton, “The Eye of Death; or, The Murder Charge”, in Manalive, New York, N.Y.: John Lane, →OCLC, part II (The Explanations of Innocent Smith), page 182

   2 more examples

   I was in the gutter, sitting my bike, willing them to die, […] or otherwise obliterated because this demanded split-second timing.

   1959, William Golding, chapter 4, in Free Fall, Harbinger Books edition, New York, N.Y.: Harcourt, Brace & World, published 1962, →OCLC, page 82

   It appears [Simon] Cowell has been taking notes from South Korea, as his next talent show Walk The Line, coming later this year, has also been game-ified: it will see singers perform, then have to make the split-second decision of whether to take a cash prize or risk advancing in the competition instead.

   2021 September 15, Laura Martin, “How Talent Shows Became TV’s Most Bizarre Programmes”, in BBC Online, archived from the original on 18 Apr 2023

   Synonyms: bat of an eye, bit, blink of an eye, crack, eyeblink, flash, glimpse, half a mo