inexorable

The story

1. Proto-Indo-European · derived from*h₃éh₁os“mouth”
2. Latin · derived frominexōrābilis“relentless, inexorable”
3. Middle French · derived frominexorable
4. English todayinexorable

From Middle French inexorable, from Latin inexōrābilis (“relentless, inexorable”) (or directly from the Latin word), from in- (prefix meaning ‘not’) + exōrābilis (“that may be moved or persuaded by entreaty; exorable”). Exōrābilis is derived from exōrāre (from exōrō (“to persuade, win over; to beg, entreat, plead”), from ex- (prefix meaning ‘out of’) + ōrō (“to beg, entreat, plead, pray; to deliver a speech, orate”), from ōs (“mouth”), from Proto-Indo-European *h₃éh₁os (“mouth”)) + -bilis (suffix forming adjectives indicating a capacity or worth of being acted upon). By surface analysis, in- + exorable.

First known use, by meaning

• from mid 16th c. Impossible to prevent or stop; inevitable.
• from mid 16th c. Unable to be persuaded; relentless; unrelenting.