Leu'co·phane (lū'ko*fān) noun [ Greek leykofanh`s appearing bright or white; leyko`s white + fai`nein to show: confer German leukophan .] (Min.) A mineral of a greenish yellow color; it is a silicate of glucina, lime, and soda with fluorine.... Found on http://www.encyclo.co.uk/webster/L/33