lumen-hour

[ loo-muh n-ouuh r, -ou-er ]
/ ˈlu mənˌaʊər, -ˌaʊ ər /

noun Optics.

a unit of luminous energy, equal to that emitted in 1 hour by a light source emitting a luminous flux of 1 lumen. Abbreviation: lm-hr

Origin of lumen-hour

First recorded in 1920–25