RhymeZone: grayscale definitions

Definitions of grayscale:

noun: (photography) A printed strip of graduated tones used to check exposure and development times.
noun: (imaging) The use of black and white, representing color with shades of gray.
adjective: (imaging) Black and white, representing color with shades of gray.
verb: (transitive) To convert to grayscale.

(Definitions from Wiktionary)