Malvineous:
Mika - Big Girl (You are Beautiful)
The Grateful Dead - I Need a Miracle
Spinal Tap - Big Bottom
Nicki Minaj - Anaconda
There are so many songs about big butts, but no songs about big tiddies. This is terribly unfair :'(
This is actually untrue. There are lots of songs around the world that either mentions or is about big tits.
My favorite example actually opens with the singer describing her tits in vivid detail. The song, Shave 'Em Dry, is about an older, large woman talking in vivid detail about her sexual prowress.

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Listen to his with headphones on, btw. It makes WAP sound like a church hymn in comparison. And to think it came out in the '30s no less.