What does aphorism mean?
The definition of aphorism
Aph”o*rism, n.
Etym: [F. aphorisme, fr. Gr. Horizon.]

A comprehensive maxim or principle expressed in a few words; a sharply defined sentence relating to abstract truth rather than to practical matters. The first aphorism of Hippocrates is, “Life is short, and the art is long.” Fleming.

Synonyms
— Axiom; maxim; adage; proverb; apothegm; saying; saw; truism; dictum. See Axiom.