Once upon a time "Escalator" was a trademarked brand name. Kleenex fought hard to retain it's trademark, and Coca-Cola lost the battle for the word "Cola", keep

Once upon a time "Escalator" was a trademarked brand name. Kleenex fought hard to retain it's trademark, and Coca-Cola lost the battle for the word "Cola", keeping only "Coke". It happens. It's part of language. Over time, former brand names lose their significance and slowly slip into common use. That is a perfectly valid way for words to be coined, and probably is the most common way. That's how language works, and it seems that the word "Google" is going that way too.