twenty-five percent vs quartern

twenty-five percent and quartern both are nouns.

Word	Noun	Adjective	Verb	Adverb
twenty-five percent	Yes	No	No	No
quartern	Yes	No	No	No

As nouns, twenty-five percent and quartern are synonyms defined as:

Other synonyms of twenty-five percent include fourth, fourth part, one-fourth, one-quarter, quarter.

twenty-five percent (noun)	quartern (noun)
one of four equal parts	one of four equal parts