mal- Look up mal- at Dictionary.com
word-forming element meaning "bad, badly, ill, poorly, wrong, wrongly," from French mal (adv.), from Old French mal (adj., adv.) "evil, ill, wrong, wrongly" (9c.), from Latin male (adv.) "badly," or malus (adj.) "bad, evil" (fem. mala, neuter malum), from Proto-Italic *malo-, from PIE *mol-o-, source also of Old Irish mell "destruction," Greek meleos "idle; unhappy," Armenian mel "sin," Lithuanian melas "lie," Latvian malds "mistake," possbily also Greek blasphemein "to slander." The semantics fit, but the exact sense of the root remains uncertain, "since it concerns a collection of largely isolated words in different IE branches" [de Vaan]. Most Modern English words with this element are 19c. coinages.