I'm aware of that, Professor. But what's your point? Your saying that does not help you any, here.
It's amusing that you're from England, and yet, you write, in English, as though it were a second language to you--one upon which you yet find yourself struggling to get a decent grip.
You did not say that a descriptor--a word--for the color, red, is your nickname; rather, you said that the color, red, is your nickname:
The antecedent of your pronoun, "It", is your phrase, "the colour red", by which you are denoting the color, red, no?
You did not say, "I like the word, 'red'....It is a nickname of mine", or "I like the descriptor, 'red'....It is a nickname of mine". Rather, you said, "I like the colour red....It is a nickname of mine".