irrefragable

The story

1. Proto-Indo-European · derived from*bʰreg-“to break”
2. Latin · derived fromir-
3. Late Latin · learned borrowing fromirrefrāgābilis“irrefragable”
4. English todayirrefragable

Learned borrowing from Late Latin irrefrāgābilis (“irrefragable”) + English -able (suffix forming adjectives with the sense ‘able or fit to be done’). Irrefrāgābilis is derived from Latin ir- (variant of in- (prefix meaning ‘not’)) + refrāgārī + -bilis (suffix forming adjectives indicating a capacity or worth of being acted upon); while refrāgārī is the present active infinitive of refrāgor (“to oppose, resist; to gainsay, thwart”) (further etymology uncertain, possibly from re- (prefix meaning ‘again’) + fragor (“a breaking, shattering; a crash; din, uproar”) (from frangō (“to break, shatter”), ultimately from Proto-Indo-European *bʰreg- (“to break”))), formed as an antonym of suffrāgōr, the first-person singular present passive indicative of suffrāgō (“to support; to vote for”).

Words from the same roots

First known use, by meaning

• from 16th c. Which cannot be refuted; clearly right, incontrovertible, indisputable, irrefutable.