ˈ ̷ ̷ˌ ̷ ̷ noun
Etymology: Middle English, from Old English bīword, from bī by + word — more at by , word
1. : a proverbial saying : proverb
the old byword of necessity being the mother of invention — A.L.Kroeber
2.
a. : one that is proverbial as a type of specified characteristics
John Henry has become a byword with them, a synonym for superstrength and superendurance — G.B.Johnson
the mountain view from its spacious glassed-in porches is a White Mountain byword — E.W.Smith
b. : an object of scorn or derision
we ourselves shall become a reproach and byword down to future ages — Benjamin Franklin
3. : epithet ; especially : a scornful epithet
4. : a word or phrase frequently used by a particular person : a favorite expression
we called him “the Deacon” because of his favorite byword “Praise be” — H.A.Chippendale