by ‧ word /ˈbaɪwɜːd $ -wɜːrd/ BrE AmE noun
1 . be a byword for something to be so well known for a particular quality that your name is used to represent that quality:
His name has become a byword for honesty in the community.
2 . [singular] a word, phrase, or saying that is very well known:
Caution should be a byword for investors.