From Middle English parles, parlous, perlous, [and other forms], a contraction of perilous (“dangerous; dreadful, terrible; morally corrupt, sinful, wicked; inauspicious, unlucky”) (and thus a doublet of perilous), from Old French perilleus, perillos, perillous, perilluse, perilleuse, perilleux (“very dangerous, perilous”) (modern French périlleux), from Latin perīculōsus (“dangerous, hazardous, perilous”), from perīculum...