welkin
Welkin (noun) means (literary) The sky, seen as a dome over the earth.
Etymology
Inherited from Middle English welkne (“weather; heavens; (earlier) cloud”), from Old English wolcnu (“sky, heavens”), the plural of wolcn (“cloud”), from Proto-West Germanic *wolkn (“cloud”), from Proto-Germanic *wulkną (“cloud”), possibly going back to Proto-Indo-European *wĺ̥ɡ-no-m, from *welg- (“damp; wet”). It is cognate with Dutch wolk (“cloud”) and German Wolke (“cloud”).