Recent Examples on the WebWell, both of those statements are arrant nonsense.CBS News, 19 Jan. 2020
Word History
Etymology
Middle English arraunt, variant of erraunt "wandering, itinerant" (reflecting lowering of ĕ to ă before r); arraunt, erraunt in sense "notorious, reprobate" (hence, "extreme") from its use in the collocation theef erraunt, erraunt theif "outlawed robber roaming the country" — more at errant
Note: The two spellings arrant and errant (and presumably the associated pronunciations) were used indiscriminately into the 17th century, after which arrant became limited to its current meaning; since Robert Baker's Reflections on the English Language (1770), usage commentators have considered errant in the sense "arrant" as an error.