Let's break down what this means:
* Nominative: This refers to the grammatical case of a noun when it acts as the subject of a sentence. It's the noun that performs the action described by the verb.
* Singular: This means that the noun refers to one thing, not multiple things.
* Noun: This is a word that refers to a person, place, thing, or idea.
Here are some examples of nominative singular nouns:
* The cat sat on the mat. ("Cat" is the subject of the verb "sat" and is singular.)
* She ate a delicious apple. ("She" is the subject of the verb "ate" and is singular.)
* John walked to school. ("John" is the subject of the verb "walked" and is singular.)
Key takeaway: A nominative singular noun is the "doer" of the action in a sentence, and it refers to just one thing.