Simple Definition of split second

from our Learner's Dictionary

split second

1 of 2

noun

: a very short period of time
In a split second, it was all over.

split-second

2 of 2

adjective

always used before a noun
1
: done very quickly
a split-second decision
2
: very accurate or precise
split-second timing

Cite this Entry

“Split second.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/split%20second. Accessed 23 Jun. 2026.

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