odd or even

or odds or evens

noun

1. any of various games of chance in which one bets on an odd or even number, as one in which two players alternately draw from a pile of an odd number of counters any desired number up to a prearranged limit, the object being to have drawn an odd number of counters at the end of the game.

Word History and Origins

Origin of odd or even¹

First recorded in 1625–35

Example Sentences

One concerns the “parity” of a graph’s vertices, meaning whether they are connected to an odd or even number of other vertices.

From Quanta Magazine

Lines for gas formed, and service stations rationed supplies, sometimes using a system in which they fueled cars on alternate days depending on whether license plates ended in odd or even numbers.

From Washington Post