I. dis ‧ col ‧ or /dɪsˈkʌlə $ -ər/ BrE AmE verb [I, T]
the American spelling of ↑ discolour
II. dis ‧ col ‧ our BrE AmE British English , discolor American English /dɪsˈkʌlə $ -ər/ verb [intransitive and transitive]
to change colour, or to make something change colour, so that it looks unattractive:
Once cut, apples quickly discolour.