From *zъlъ (“bad”) + *-o. *<span class="searchmatch">zъlo</span> n evil * -ъmь in North <span class="searchmatch">Slavic</span>, -omь in South <span class="searchmatch">Slavic</span>. East <span class="searchmatch">Slavic</span>: Old East <span class="searchmatch">Slavic</span>: зъло (zŭlo) Old Ruthenian: зло (zlo)...
From <span class="searchmatch">Proto</span>-Balto-<span class="searchmatch">Slavic</span> *źulas, perhaps from a <span class="searchmatch">Proto</span>-Indo-European *ǵʰwel- (“to lie, deceive, bend”). Cognate with Lithuanian žulas (“rough”), (dialectal)...