milk chocolate
dark chocolate
video game
board game
hand soap
bath soap
toothbrush
hair brush
baseball
baseball cap
blue jeans
wristwatch
headband
I could go on, but the point is pretty clear isn't it? adjective-noun, edjective-noun, etc. If you used the adjective part to refer to the word, no one would know what you were talking about. Would you like some dark for dessert? Did you hair your hair this morning?
so just two more...
soda water
soda pop
That is all.
(Yes, i'm biased, suck it =)