
1) Imperial unit
Found on
https://www.crosswordclues.com/clue/foot-candle

A foot-candle (sometimes foot candle; abbreviated fc, lm/ft2, or sometimes ft-c) is a non-SI unit of illuminance or light intensity widely used{cn|date=April 2013} in the United States in photography, film, television, conservation lighting, greenhouse horticulture, the lighting industry, construction-related engineering and in building codes. The...
Found on
http://en.wikipedia.org/wiki/Foot-candle

• The amount of illumination produced by a standard candle at a distance of one foot.
Found on
http://thinkexist.com/dictionary/meaning/foot_candle/

A unit of illuminance; equal to one lumen per square foot. Related categories • UNITS • SOLAR ENERGY AND POWER
Found on
http://www.daviddarling.info/encyclopedia/F/AE_foot_candle.html
Foot candle (Photom.) The amount of illumination produced by a standard candle at a distance of one foot.
Found on
http://www.encyclo.co.uk/webster/F/55

footcandle, foot candle Illumination or brightness equivalent to one lumen per square foot; replaced in the SI system by the candela; or the luminous intensity, in a given direction, of a source that emits monochromatic radiation of frequency.
Found on
http://www.wordinfo.info/words/index/info/view_unit/363/

(fc) Standard unit of measure for illumination on a surface. The Average foot-candle level on a square surface is equal to the lumens striking the surface, divided by the area of the surface.
Found on
http://www.youngco.com/young2.asp?ID=4&Type=3

An illumination light unit used mostly in American CCTV terminology. It equals 10.76 times the illumination value in lux (1m2 = 10.76 sq ft).
Found on
http://www.zoo.co.uk/~z0001325/Glossary.html

Measurement of light. One foot candle is the light of one candle, one foot away. Many light meters will use foot candles as a starting number, which then must be converted into an f-stop based on the sensitivity of the film you are using. (Because of the great variety of different film speeds it is sometimes ambiguous to talk too much about foot ca...
Found on
https://www.encyclo.co.uk/local/21112

a measurement of light intensity
Found on
https://www.encyclo.co.uk/local/22440

A unit of illuminance; equal to one lumen per square foot.
Found on
https://www.encyclo.co.uk/local/22819

a unit of illuminance or illumination, equivalent to the illumination produced by a source of one candle at a distance of one foot and equal to one lumen incident per square foot. Abbr.: FC
Found on
https://www.infoplease.com/dictionary/foot-candle

The quantity of light at a point on a plane surface one foot from and perpendicular to a standard candle.
Found on
https://www.xrite.com/learning/other-resources/glossary
No exact match found.