solecism

Borrowed from Middle French solecisme, soloëcisme (French solécisme) or its etymon Latin soloecismus, from Ancient Greek σολοικισμός (soloikismós), from σόλοικος (sóloikos, “speaking incorrectly”), from Σόλοι (Sóloi), an ancient Athenian colony in Cilicia whose inhabitants spoke a dialect regarded by Athenians as a corrupted and barbarous form of Attic Greek. Compare Atticism.