Throughout the centuries and decades of human life span, words and their meanings have changed perspective or have been eliminated all together. No one says "thou" anymore and gay used to mean happy as early as the 1950's. Tossed in among our language are slang words such as cool, super, awesome, bling-bling and many more. Some stick around for awhile and others depart with the fashion trends of that decade or era. Thrown into the mix are also words that come about with the technology age such as internet, jpegs (pronounced jay-pegs), bytes, bitmap and a slew of other terms.
What have also made it into our language are brand names. Some brands are so popular for one particular item that the brand name has been associated with the actual product itself.
Some common examples are:
Kleenex

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The proper term is "facial tissue" and Kleenex is the brand name. In this writer's opinion, this is the most common brand name used in replace of the item. On school supply lists it even states "2 boxes Kleenex" and yet when you send a generic brand they don't complain. It literally meant the facial tissue and not the brand name. Pampers

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Otherwise known as "diapers;" Pampers is the brand name for disposable diapers meant for infants. But often even adult disposable undergarments are called "pampers." Coincidentally, Depends® is a brand name for adult disposable undergarments but often used as a word meaning any adult disposable undergarment. Coke

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I came across this one after I moved to New Mexico from Wisconsin. In the north we drank "pop" and a Coke meant a Coca-Cola. On my first date after my move to New Mexico the fellow asked me if I wanted to stop after the movies for a coke. I agreed, and we stopped at Sonic Drive-In. He promptly ordered a drink that had not one ounce of Coke in it. When I questioned him he said "coke" meant anything to drink. It didn't even have to be carbonated. Coca Cola is a derivative of coca leaves and kola nuts. The inventor changed the "k" to a "c" for appearance. The word Coke has become a nickname of sorts. Arm & Hammer

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Perhaps a lesser used brand name replacement is this brand for baking soda. I have heard a handful of people say they need to be some "arm and hammer" and it is often combined like one word. The name and logo is based on the arm and hammer of the Vulcan, the Roman God of fire and metalworking. Tylenol

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Unlike its counterparts, Aleve or Bayer for example, Tylenol has been used to replace any pain-relieving medication whether it is with or without aspirin. Xerox

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Derived from the term "xerography" which is a word derived from the Greek xeros (dry) and graphos (writing). The company was founded as The Haloid Company in 1906, launched its first XeroX copier in 1949, and changed its name to Haloid Xerox in 1958. The brand name of the machine is Xerox and the actual machine itself is a "photo copier." But, often in offices it is heard "Xerox me a copy" or something similar. Google

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While not so much a brand name as service name, Google is synonymous with a search engine, despite it offering other services. It is so popular that many internet users simply state "Google it" when they mean "search for it." It has even been used in movies and television. Google is a deliberate misspelling of the word "googol" which reflects the company's mission of organizing the massive amounts of information online. Nabs

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Here in the south, it is common to hear someone say "I want a pack of Nabs." What they mean is any small package of cheese or peanut butter filled cracker snacks. The real Nabs were put out by the Nabisco company but have been gone since 1928. Today, Lance is the pre-dominant cracker company in the south but no one asks for "a pack of Lances." Ouija

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Often this name is not even realized as being misused. Parker Brothers has created their own version of what is really known as a spirit board, psychic board or talking board. Ouija is the name of their product much like Monopoly or Scrabble. Play-Doh

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A soft and pliable product, this colored dough is great fun for children of all ages. No one even seems to know what the call the stuff if not by its brand name of Play-Doh. Modeling clay is perhaps the most accurate term for this fun product. But, Play-Doh has become synonymous with the clay and if you say you are buying "Play-Doh" everyone knows what you mean. Legos

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Again, this toy's brand name has become synonymous to mean the toy. Legos is a brand name and the product is a building block, often with the word "connecting" preceding it. But ask any child what Legos are and they will know immediately. Nike

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The 80's and 90's saw the emerging popularity of the Nike shoe. So popular is the shoe that is has come to mean any pair of tennis or athletic shoe.
So there you have it, brand names that get misused as the product name. When these companies no longer exist or no long produce the product will people still refer to them as Kleenex, or Nikes or ask for a Coke and a pack of Nabs? Probably so, for as they say, "old habits die hard."
(All pictures and brand names are registered trademarks).