ENGLISH
REFERENCE

lambert

n. countable
C2 Proficiency US //ˈɫæmbɝt// UK //lˈæmbət// lam·bert

n. a unit used by scientists to measure how much light comes off a flat surface.

n. a non-SI unit of luminance equal to one lumen per square centimetre. Named after the physicist Johann Heinrich Lambert; often used in older scientific literature to describe the brightness of a perfectly diffusing surface.


SIMPLE

The scientist measured the brightness in Lamberts.

CONTEXTUAL

Engineers calculated the screen's brightness in Lamberts to ensure it remained visible under direct sunlight.

COMPLEX

While the candela per square metre is now the standard metric unit, the Lambert remains a historical reference point in early twentieth-century optical physics and lighting design.

Origin

From Middle English Lambert, from Old French Lambert, a saint's name (of a Bishop of Maastricht) brought to England by the Normans, from Proto-West Germanic Landaberht, from land (“land”) + *berht (“bright”). Cognate with Old English Landbeorht, Old High German Lantberht, Dutch Lambrecht.

Usage

Usually capitalised as it is named after a person; often used in the plural form when providing specific measurements.

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