Why is an orange called an orange but grapes aren't called purples?

The colour was named after the fruit, so at one point in time the colour of oranges were red.

I honestly just think about my past mistakes.
For an hour.

*googles* ... TIL that the name "grapefruit" is a reference to the fact that they grow in clusters. Also, that grapefruits are an accidental hybrid species arising from two introduced species. Additionally, I learned that the taxonomy of the genus Citrus is annoyingly complex.

Because grapes can also be green?

Shaving takes a while.. Especially when you are blind in the shower