Main Difference
The main difference between Noun and Pronoun is that the Noun is a part of speech in grammar denoting a figurative or real thing or person and Pronoun is a word or form that substitutes for a noun or noun phrase.
Noun
A noun (from Latin nōmen, literally meaning “name”) is a word that functions as the name of some specific thing or set of things, such as living creatures, objects, places, actions, qualities, states of existence, or ideas. However, noun is not a semantic category, so that it cannot be characterized in terms of its meaning. Thus, actions and states of existence can also be expressed by verbs, qualities by adjectives, and places by adverbs. Linguistically, a noun is a member of a large, open part of speech whose members can occur as the main word in the subject of a clause, the object of a verb, or the object of a preposition.Lexical categories (parts of speech) are defined in terms of the ways in which their members combine with other kinds of expressions. The syntactic rules for nouns differ from language to language. In English, nouns are those words which can occur with articles and attributive adjectives and can function as the head of a noun phrase.
Pronoun
In linguistics and grammar, a pronoun (abbreviated PRO) has been theorized to be a word that substitutes for a noun or noun phrase. It is a particular case of a pro-form.
Pronouns have traditionally been regarded as one of the parts of speech, but some modern theorists would not consider them to form a single class, in view of the variety of functions they perform cross-linguistically. An example of a pronoun is “their”, which is both plural and singular. Subtypes include personal and possessive pronouns, reflexive and reciprocal pronouns, demonstrative pronouns, relative and interrogative pronouns, and indefinite pronouns.The use of pronouns often involves anaphora, where the meaning of the pronoun is dependent on an antecedent. For example, in the sentence That poor man looks as if he needs a new coat, the antecedent of the pronoun he is dependent on that poor man.
The adjective associated with pronoun is pronominal. A pronominal is also a word or phrase that acts as a pronoun. For example, in That’s not the one I wanted, the phrase the one (containing the prop-word one) is a pronominal.
Noun (noun)
A word that can be used to refer to a person, animal, place, thing, phenomenon, substance, quality, or idea; one of the basic parts of speech in many languages, including English.
Noun (noun)
Either a word that can be used to refer to a person, animal, place, thing, phenomenon, substance, quality or idea, or a word that modifies or describes a previous word or its referent; a substantive or adjective, sometimes also including other parts of speech such as numeral or pronoun.
Noun (verb)
To convert a word to a noun.
Pronoun (noun)
A type of anaphorically to another noun or noun phrase, but which cannot ordinarily be preceded by a determiner and rarely takes an attributive adjective. English examples include I, you, him, who, me, my, each other.
Noun (noun)
a word (other than a pronoun) used to identify any of a class of people, places, or things (common noun), or to name a particular one of these (proper noun).
Pronoun (noun)
a word that can function as a noun phrase used by itself and that refers either to the participants in the discourse (e.g. I, you) or to someone or something mentioned elsewhere in the discourse (e.g. she, it, this).