Key Difference:  Abstract nouns are used to denote an idea, state, a feeling, a quality or a characteristic, whereas collective nouns are used to denote  groups.

A noun is a part of speech that identifies a person, a thing, an idea, quality or state. There are various types of nouns like common nouns, proper nouns, concrete nouns, abstract nouns and collective nouns. Thus, abstract noun and collective noun are two different types of nouns.

An abstract noun is used to refer an intangible thing like a state, event, concept, feeling, quality etc. All the abstract nouns have no physical existence. For example, happiness is a state of being happy. It is intangible in nature, but it is denoting a state thus, it falls in the category of an abstract noun. An abstract noun is used to denote something that cannot be seen, touched, heard, smelt or tasted. Abstract noun is the opposite of concrete noun. Here is the list of some common abstract noun:

Love, peace, reality, truth, faith, kindness, charity, hate, calm, anger, loyalty, childhood, compassion, friendship, joy, pleasure, delight, etc,. For example:-

My childhood toys fill my heart with joy.

In this sentence, childhood and joy both are abstract nouns. Childhood is referring to a stage of a person’s life and joy is a feeling. Thus, both are considered as abstract nouns. Abstract nouns are often feelings or emotions. It can be of two types: countable and uncountable. Courage, freedom, etc, are examples of abstract uncountable nouns, whereas a joke, an hour, etc. are referred as abstract countable nouns. A noun may also belong to more than one category. For example, happiness is both a common noun as well as an abstract noun. Most of the abstract nouns end with suffixes likes

-ism (nationalism), -ment (arguement), -ity (personality), -ness (faithfulness), -tion (separation), -age (courage), -ship (friendship), etc.,

 A collective noun is used to refer words used for a group of specific people, animals and items. For example, a group of lions is known as pride.

Our family had gone to watch a movie.

In this sentence, family refers to all members of the family and is denoting a group of members. Thus, family is a collective noun. Collective nouns are considered to be a subset of count nouns because they denote a group of countable nouns as a whole unit. For example, a dozen contains 12 items. A collective noun can usually be treated as singular or plural. If a singular verb is used then the noun treats it as a single entity, whereas if a plural verb is used then the noun is referred as consisting of a group of individuals.

Hence, both are different kinds of nouns and denote totally different types of nouns. An abstract noun is associated with intangible things, whereas collective noun is associated with grouping of things.

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