To ignore is always willful, isn’t it?
But I think one of the examples I picked has finally talked me out of this. I would happily use “vacant” to also describe a place that has never been occupied, so it didn’t require vacating to be vacant. In that case, vacate means to make vacant, not vice versa. I’ll apply that to ignore/ignorant, and I think I finally understand how people have been so comfortable with that definition.
Jess and Rob on Words Unraveled talk about color word origins, and their discussion is illuminating about the cultural variance in perception of color. Now I am at peace with all the seemingly weird color names for things.
For a quicker tour, Vox talks about the order that languages fill in color words as cultures begin to refine their distinction.