|candela (kænˈdiːlə, -ˈdeɪlə)|
|cd, candle, Also called: standard candle the basic SI unit of luminous intensity; the luminous intensity in a given direction of a source that emits monochromatic radiation of frequency 540 × 1012 hertz and that has a radiant intensity in that direction of (1/683) watt per steradian|
|[C20: from Latin: |
|a printed punctuation mark (‽), available only in some typefaces, designed to combine the question mark (?) and the exclamation point (!), indicating a mixture of query and interjection, as after a rhetorical question.|
|a gadget; dingus; thingumbob.|
candela can·del·a (kān-děl'ə)
A unit of measurement of luminous flux, equal to the amount of light given out through a solid angle by a source of one candela radiating equally in all directions. Also called candle.
|candela (kān-děl'ə) Pronunciation Key
The SI unit used to measure the brightness of a source of light (its luminous intensity). By definition, one square centimeter of a blackbody at the freezing point of platinum emits one-sixtieth of a candela of radiation. See Table at measurement. See also lumen, luminous flux.
unit of luminous intensity in the International System of Units (SI), defined as the luminous intensity in a given direction of a source that emits monochromatic radiation of frequency 540 1012 hertz and has a radiant intensity in that same direction of 1683 watt per steradian (unit solid angle). The candela has replaced the standard candle or lamp as a unit of luminous intensity in calculations involving artificial lighting and is sometimes called the "new candle."
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