| Subject | English | Russian |
| gen. | a split second | доля секунды (Anglophile) |
| gen. | a split second before | за секунду до (Alexey Lebedev) |
| gen. | a split second before | за долю секунды до (Alexey Lebedev) |
| gen. | be gone in a split second | как ветром сдуть (Anglophile) |
| idiom. | for a split second | на короткий момент (yashenka) |
| idiom. | for a split second | за долю секунды (yashenka) |
| gen. | for a split second | на долю секунды (clck.ru dimock) |
| idiom. | in a matter of a split second | за долю секунды (Two hours after the mothership blinked off after 30 minutes, a cube-shaped craft went zipping along over the treetops where the mother ship had been. In a matter of a split second, the cube crossed the water and was one house away from me hovering, completely silent. The entire area was bathed in golden light: it had 16 lights per side. Ten minutes later, two cubes stuck together zipped over the treetops over the mainland and as I watched, they unzipped. All blue lights on one, all red lights on the other. (youtube.com) ART Vancouver) |
| gen. | in a split second | в долю секунды (Tundra_cold) |
| gen. | in a split second | моментально |
| gen. | in a split second | за долю секунды (Maria Klavdieva) |
| gen. | in a split second | моргнуть не успеешь |
| idiom. | make a split-second decision | принять мгновенное решение (The 30-year-old had to make a split-second decision – either slam on the brakes and come to a stop right next to the equally startled bear, or attempt to scoot around him and keep going.  nsnews.com ART Vancouver) |
| idiom. | make a split-second decision | мгновенно принять решение (The 30-year-old had to make a split-second decision – either slam on the brakes and come to a stop right next to the equally startled bear, or attempt to scoot around him and keep going. nsnews.com ART Vancouver) |