A euphemism for rough sex, where the walrus is the female/or receiving partner involved, and the belt sander is the person doing the penetrating.
1. I beltsanded the walrus last night.

2. I'm gonna beltsand YOUR Walrus.

3. Dude! You beltsanded my walrus!

4. Yeah! I am Beltsanding the Walrus!
by Gaywadmadesto February 16, 2009
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