byword
n. US //ˈbaɪˌwɝd// UK //bˈaɪwɜːd// by·word
From Middle English byword, byworde (“proverb”), from Old English bīword, bīwyrd, bīwyrde (“proverb, household word", also "adverb”), from Proto-West Germanic *bīwurdī, equivalent to by- + word. Compare Latin proverbium, which byword may possibly be a translation of. Cognate with Old High German pīwurti (“proverb”). Compare also Old English bīspel (“proverb, example”), bīcwide (“byword, proverb, tale, fable”), Dutch bijwoord (“adverb”).