I know the basics that I learnt in kindergarten of course, but beyond that, after years of majoring in photography at university, colours to me are broken up into cyan/red, magenta/green and yellow/blue.
This has been a bit of a problem when listing items online, trying to describe colours. But, I have a new best (website) friend; Wikipedia's List of Colours. It helps me differentiate between persimmon and terracotta, between sea green and forest green, between cobalt blue and royal blue.
I'm slowly learning!