The Meaning of Noun | Definition of Noun

a noun is a word that refers to a person, place, or thing.

Nouns can be singular (‘one sandwich’) or plural (‘two sandwiches’), although some nouns take the same form regardless (‘one sheep,’ ‘two sheep’). Nouns can also refer to concepts (information) that cannot be counted and singular entities (Neptune) that cannot be pluralized.
Sentences can have one noun (“Theo ran quickly.”) or more than one (“Theo ran quickly across the field.”) but some sentences don’t have any (“Run, quickly!”).
Types of nouns
1) Proper nouns
2) Common nouns
3) Concrete nouns
4) Abstract nouns
5) Collective nouns
6) Non-Countable Nouns
7) Compound Nouns