(noun, adjective)


1. consisting of or especially arranged in sets of four

- quaternate leaves

- a quaternary compound

Similar word(s): multiple, quaternate

2. coming next after the third and just before the fifth in position or time or degree or magnitude

- the quaternary period of geologic time extends from the end of the tertiary period to the present

Similar word(s): ordinal, fourth


1. last 2 million years

Definition categories: time

2. the cardinal number that is the sum of three and one

Similar word(s): four, foursome, quadruplet, quartet, quaternion, quaternity, tetrad

Definition categories: quantity, digit, figure