Is MY a common noun

Answer 1

Count nouns or countable nouns are common nouns that can take a plural, can combine with numerals or counting quantifiers (e.g., one, two, several, every, most), and can take an indefinite article such as a or an (in languages which have such articles). Examples of count nouns are chair, nose, and occasion. Mass nouns or uncountable (or non-count) nouns differ from count nouns in precisely that respect: they cannot take plurals or combine with number words or the above type of quantifiers. For example, it is not possible to refer to a furniture or three furnitures. This is true even though the pieces of furniture comprising furniture could be counted. Thus the distinction between mass and count nouns should not be made in terms of what sorts of things the nouns refer to, but rather in terms of how the nouns present these entities.Many nouns have both countable and uncountable uses; for example, soda is countable in "give me three sodas", but uncountable in "he likes soda". Collective nouns are nouns that – even when they are inflected for the singular – refer to groups consisting of more than one individual or entity. Examples include committee, government, and police. In English these nouns may be followed by a singular or a plural verb and referred to by a singular or plural pronoun, the singular being generally preferred when referring to the body as a unit and the plural often being preferred

Answer 2

a class of entities

Answer 3

The word 'my' is not a noun.

The word 'my' is a pronoun called a possessive adjective.

A possessive adjective is a word that is placed before a noun to show that the noun belongs to the person speaking.

The possessive adjectives are: my, your, our, his, her, their, its.

Example: My bicycle is new. My parents gave it to me for my birthday.