1. The Specific Becomes Generic:
* Example: "Band-Aid" originally referred to a specific brand of adhesive bandage. Over time, people started using "Band-Aid" to refer to any adhesive bandage, regardless of brand.
2. Reference to a Type, Not a Specific Instance:
* Example: "Xerox" was a specific brand of photocopying machine. Now, people use "Xerox" as a verb ("I need to Xerox this document") meaning "to make a copy."
3. The Original Meaning Fades:
* Example: "Levi's" was a specific brand of jeans. Now, people use "Levis" to refer to a style of jeans.
4. Social and Cultural Context:
* The shift from proper noun to common noun often happens due to cultural factors. For example, "Kleenex" became synonymous with facial tissues because of its widespread use and marketing.
Note:
* Not all proper nouns can become common nouns. For example, "Queen Elizabeth" is a specific person and will likely never become a general term.
* This process often happens over time and depends on the usage and acceptance of language.
* Some people may consider it incorrect to use a proper noun as a common noun, while others might find it perfectly acceptable.