sinumbra lamp

or si·num·bral lamp

[si-nuhm-bruh]

noun

an unshaded sperm-oil lamp consisting of a translucent glass globe supported on a pedestal: a form of astral lamp.

Origin of sinumbra lamp

1825–35; < Latin sin(e) without + umbrā shade, shadow
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019