"Common" refers to something that is shared or widespread. In the context of nouns, it signifies that the noun refers to a general category or class of things, rather than a specific individual or unique item.
"Noun" refers to a word that names a person, place, thing, or idea.
Therefore, a "common noun" is a word that names a general category or class of things, which is shared by many individuals.
For example:
* "Dog" is a common noun because it refers to a general category of animals, not a specific individual dog.
* "Book" is a common noun because it refers to a general category of printed materials, not a specific book.
The term "common noun" originated from the concept that these words are commonly used and understood by everyone, unlike proper nouns which refer to specific entities like "John" or "New York City."