From *sì- + *-zъ, from <span class="searchmatch">Proto</span>-Balto-<span class="searchmatch">Slavic</span> *śī́ˀ-, from <span class="searchmatch">Proto</span>-Indo-European *(s)ḱih₃-, from *(s)ḱeh₃- (“to shade”). *<span class="searchmatch">sìzъ</span> dove-coloured, warm grey, bluish...
Expected reflex of Old East <span class="searchmatch">Slavic</span> сизъ (sizŭ), from <span class="searchmatch">Proto</span>-<span class="searchmatch">Slavic</span> *<span class="searchmatch">sìzъ</span>. Cognate with Russian си́зый (sízyj). *си́зый • (*sízyj) dove-coloured, warm grey...