Surely the size of the spider is often the most fundamental aspect? “Don’t look now, but there’s a huge brown spider behind you.” If “big spider” were a species then it’s inseparable (as benelliott points out) because it’s a species name, but that’s a different story. I wouldn’t talk about a green enormous chameleon even if I knew that the chameleon was about to change colors without changing its size.
Surely the size of the spider is often the most fundamental aspect? “Don’t look now, but there’s a huge brown spider behind you.” If “big spider” were a species then it’s inseparable (as benelliott points out) because it’s a species name, but that’s a different story. I wouldn’t talk about a green enormous chameleon even if I knew that the chameleon was about to change colors without changing its size.