cupola

Concise Oxford English Dictionary © 2008 Oxford University Press:
cupola /ˈkjuːpələ/

▶noun

• 1 a rounded dome forming or adorning a roof or ceiling.

• 2 a gun turret.

• 3 (also cupola furnace) a cylindrical furnace for refining metals.

– derivatives
cupolaed /-ləd/ adjective.

– origin C16: Ital., from late L. cupula ‘small cask or burying vault’, dimin. of cupa ‘cask’.