[ˈl(j)uːmɛn], (Noun)

Definitions:
- the SI unit of luminous flux, equal to the amount of light emitted per second in a unit solid angle of one steradian from a uniform source of one candela


Phrases:

Origin:
late 19th century: from Latin, literally ‘light’

[ˈl(j)uːmɛn], (Noun)

Definitions:
- the central cavity of a tubular or other hollow structure in an organism or cell
(e.g: the stomach empties food into the lumen of the small intestine)


Phrases:

Origin:
late 19th century: from Latin, literally ‘opening’