dome 
(dōm)
(dōm)n.
1.
a. A roof or vault having a circular, polygonal, or elliptical base and a generally hemispherical or semispherical shape.
b. A geodesic dome.
2. A domelike structure or object.
3. Geology Any of various natural structures having a rounded shape, especially:
a. A system of strata that is uplifted in the center, forming a concentric anticline.
b. A mass of granite that has been weathered into a rounded shape by exfoliation.
c. A mound formed by the extrusion of viscous lava from a volcano.
4. Chemistry A form of crystal with two similarly inclined faces that meet at an edge parallel to the horizontal axis.
5. Slang The human head.
6. Archaic A large, stately building.
v. domed, dom·ing, domes
v.tr.
1. To cover with or as if with a dome.
2. To shape like a dome.
v.intr.
To rise or swell into the shape of a dome.
[From French dôme, dome, cathedral (from Italian duomo, cathedral, from Latin domus, house; see dem- in the Appendix of Indo-European roots) and from French dôme, roof (from Provençal doma, from Greek dōma, house; see dem- in the Appendix of Indo-European roots).]
domal (dōməl) adj.
dome
dometop: c. 685-691 ad Dome of the Rock
Jerusalem
bottom: lava dome within Panum Crater, near Mono Lake
Lee Vining, California