1. The quality of an object or substance with respect to light reflected by the object, usually determined visually by measurement of hue, saturation, and brightness of the reflected light; saturation or chroma; hue.
2. One of the words that's most popularly debated about the correct spelling of. Color vs Colour.
In the USA the spelling of the word is 'color'. Many "Yankophiles" (people that live outside of the USA, but admire the USA) also spell it this way.
In the UK, Canada, New Zealand, Australia, etc. the correct spelling of the word is 'colour'.
Anglophiles in the USA (Americans that admire England) also spell the word 'colour'.
There's no real correct way to spell the word, if it's officially adopted as the correct spelling there. That's why in the US, they speak American-English, not exactly English per se.
British person: So yh, mate. The colour of my car is red.
American person: wtf. u spelled color wrong.
British person: no, u did. the english language originated here. so colour is correct.
Open minded person: Shut up both of you. Both 'colour' and 'color' are both correct. You're on the internet speaking internationally, so technically they're both right.
British and American people: .....