Discolouration (noun)
alternative spelling of discoloration
Discoloration (noun)
The act of discoloring, or the state of being discolored; alteration of hue or appearance.
Discoloration (noun)
A discolored spot; a stain.
Wiktionary
Discoloration (noun)
the process of becoming discoloured, or the state of being discoloured
“a bluish discoloration of the skin”
“teeth with amalgam fillings may run the risk of discoloration”
Oxford Dictionary