Reading Wikipedia's article has me questioning the information in my above post. According to Wikipedia, the name comes from it being manufactured from "cotton

Reading Wikipedia's article has me questioning the information in my above post. According to Wikipedia, the name comes from it being manufactured from "cotton duck" (not because water rolls off it like a duck). Then a derived product became popular for wrapping air ducts, and the name evolved to duct tape. Then someone trademarked "Duck Tape" and revived the old name. I'm not sure anymore about the true origins of the terms, but I still maintain that "duck tape" and "duct tape" are both acceptable names (trademark issues aside).