Is it 'duct' or 'duck' tape?

A common mispronunciation of duct tape is "duck" tape, but it may not be much of a mistake at all.
A common mispronunciation of duct tape is duck tape, but it may not be much of a mistake at all.

Duck Tape 1.88 x 20 yd Purple Duct Tape - 283138

Duck® Brand Ducklings Mini Duck® Tape Color Duct Tape - Orange, 0.75 x 180 Inch - Pay Less Super Markets

18 Clever Uses for Duct Tape

Where Can I Find Good Duct/duck Tape? Years Ago I Had A, 58% OFF

The best duct tape - Duck, Gorilla, 3M or something else? - The

Duck Tape® Brand 1.88 in. x 55 yd. Utility Duct Tape, Silver (242946) - Yahoo Shopping

Where Can I Find Good Duct/duck Tape? Years Ago I Had A, 58% OFF

The best duct tape - Duck, Gorilla, 3M or something else? - The

Duck 1.88 X 20yd Duct Industrial Tape White : Target

Duck 1.88 in. x 10 yds. Mustache Duct Tape 280912 - The Home Depot

Which Duct Tape Brand is the Best? Let's find out!