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Synonyms for Quaternary (same or very similar meaning)

WordNet sense 1 (last 2 million years):
Age of Man, Quaternary period

WordNet sense 2 (the cardinal number that is the sum of three and one):
four, foursome, quadruplet, quartet, IV, quatern, quaternion, quaternity, tetrad, Little Joe

WordNet sense 3 (consisting of or especially arranged in sets of four):

WordNet sense 4 (having or involving or consisting of more than one part or entity or individual):

WordNet sense 5 (coming next after the third and just before the fifth in position or time or degree or magnitude):

WordNet sense 6 (being or denoting a numerical order in a series):

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