Comparing Common Nouns with Proper Nouns 

Common nouns are nouns that name generalized entities. For example; boy, girl, man, city, house, country, dogs, cats, etc. They are nouns that do not name specific entities (people, or objects), but they generalize them by virtue of shared features. For example; every boy has a male reproductive organ, and is incapable of conceiving, whether they are tall or short, white or black, handsome or not, etc. So, if Ken and James are 16 year olds and they have these features, they are, naturally, boys. Common nouns do not name specific entities, but they give generalized names for entities with shared features.

(Note: Common nouns start with small letters, and they can be preceded by determiners and adjectives.)

Proper nouns on the other hand are different. Unlike common nouns, which give generalized names for entities with shared features, proper nouns name specific entities (persons, or objects).

(Note: Proper nouns must start with a capital letter, and they do not have adjectives, or determiners e g the, their, those, my, etc,., preceding them.)

They are nouns that are very specific in naming. For example;

Joshua, Ashley, New York, Great Britain, England, McDonald's, ShopRite, MTN, etc. These are names of specific persons, places, and even brands. Proper nouns refer directly to people and do not group them like common nouns.

Here are some examples that show the differences between proper nouns and common nouns:

1. James (prop.no) — Boy (com.no)

2. Lagos (prop.no) — City (com.no)

3. Mr. Cuddles (prop.no) — Dog (com.no)

4. Britain (prop.no) — Country (com.no)

5. McDonald's (prop.no) — Eatery (com.no)

So, common nouns are different from proper nouns even though they are united by virtue of naming entities. Common nouns are nouns that name generalized entities—they can be determined using Hyponymy. For example; Lion, Cheetah, Leopard, Jaguar — Big Cats. "Big Cats" is a common noun that collectively names lions, tigers, cheetahs, etc. While the individual names of the animals that common nouns name in a generalized manner are proper nouns.

(Note: Some linguists argue in favour of "Proper names" e.g King Henry the Third, Queen Elizabeth, etc. When a person's name has honorary embeddings by which they are referred to, those names must be in capital letters as their names. Though other linguists argue that they are still proper nouns.)