Definition of "illuminance" [illuminance]

• See illumination. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "Initially, the oil was used as a lubricant for the railroad industry and as an illuminance."
• "A consequence of the putting into practice of so great an illuminance is that the luminance in the range of vision can no more be an optimal one, if no coloured surfaces are used in the working room."
• "Illumination or illuminance in various systems of units lx ph fc"