illuminance
illuminance · illuminances
The luminous flux incident on unit area of a surfaceThe luminous flux incident on unit area of a surface; commonly measured in lux (lumen/metre²) or otherwise foot-candles. The illuminance of a star upon the earth is frequently measured on a negative logarithmic scale referred to as its apparent magnitude, which see.
Meaning
1 senses(countable, uncountable)The luminous flux incident on unit area of a surface; commonly measured in lux (lumen/metre²) or otherwise foot-candles. The illuminance of a star upon the earth is frequently measured on a negative logarithmic scale referred to as its apparent magnitude, which see.
the luminous flux incident on a unit area
Forms
plural: illuminances| Singular | illuminance |
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| Plural | illuminances |
regular
Synonyms
1 synonymsClose in meaning
- the luminous flux incident on a unit area:illumination
Lessons for this word
1 lessons- A1Countable and uncountable nouns — Because it can be uncountable