Because checking out 'Genericised Trademarks' on Wikipedia led me to this list:

A few examples of trademarks which have lost their legal protection in the US are:
Aspirin, originally a trademark of Bayer AG
Escalator, originally a trademark of Otis Elevator Company[4]
Thermos, originally a trademark of Thermos GmbH
Yo-yo, originally a trademark of Duncan Yo-Yo Company
Zipper, originally a trademark of B.F. Goodrich[5]
Kerosene, originally a trademark of Abraham Gesner
Hoover, originally a trademark of The Hoover Company
Band-Aid, originally a trademark of Johnson & Johnson
Butterscotch, originally a trademark of Parkinsons
Frisbee, originally a trademark of Wham-O
Heroin, originally a trademark of Bayer

Yes, Heroin TM! Amazing.

The German drug company Bayer named its new over the counter drug "Heroin" in 1895.[7] The name was derived from the German word "heroisch" (heroic) due to its perceived "heroic" effects upon a user.[7] However it was chiefly developed as a morphine substitute for cough suppressants that did not have morphine's addictive side-effects; morphine at the time was a popular recreational drug so Bayer wanted to find a similar but non-addictive substitute to market.[8] However, contrary to Bayer's advertising as a "non-addictive morphine substitute," - oh LOL!

Christ...