"round, vaulted roof," 1656, from Fr. dome,
from Prov. doma,
from Gk. doma
"house, housetop" (especially a style of roof from the east), related to domos
"house" (see domestic
). In the Middle Ages, Ger. dom
and It. duomo
were used for "cathedral" (on the notion of "God's house"), so Eng. began to use this word in the sense "cupola," an architectural feature characteristic of It. cathedrals. Used in U.S. also with ref. to round summits of mountains.