quaternion vs four

quaternion and four both are nouns.

Word	Noun	Adjective	Verb	Adverb
quaternion	Yes	No	No	No
four	Yes	Yes	No	No

As nouns, quaternion and four are synonyms defined as:

quaternion and four: the cardinal number that is the sum of three and one

Other synonyms of quaternion include 4, foursome, IV, Little Joe, quadruplet, quartet, quatern, quaternary, quaternity, tetrad.

quaternion (noun)	four (noun)
the cardinal number that is the sum of three and one	a playing card or domino or die whose upward face shows four pips
	the cardinal number that is the sum of three and one

quaternion (adjective)	four (adjective)
	being one more than three