Nay is an adverb. 1.  An adverb is a word added to a verb, a participle, an adjective, or an other adverb; and generally expresses time, place, degree, or manner.

But is a conjunction. 1.  A conjunction is a word used to connect words or sentences in construction, and to show the dependence of the terms so connected.

O is an interjection. 1.  An interjection is a word that is uttered merely to indicate some strong or sudden emotion of the mind.

Man is a common noun, of the second person, singular number, masculine gender, and nominative case. 1.  A noun is the name of any person, place, or thing, that can be known or mentioned. 2.  A common noun is the name of a sort, kind, or class, of beings or things. 3.  The second person is that which denotes the hearer, or the person addressed. 4.  The singular number is that which denotes but one. 5.  The masculine gender is that which denotes persons or animals of the male kind. 6.  The nominative case is that form or state of a noun or pronoun, which usually denotes the subject of a finite verb.

Who is an interrogative pronoun, of the third person, singular number, masculine gender, and nominative case. 1.  A pronoun is a word used in stead of a noun. 2.  An interrogative pronoun is a pronoun with which a question is asked. 3.  The third person is that which denotes the person or thing merely spoken of. 4.  The singular number is that which denotes but one. 5.  The masculine gender is that which denotes persons or animals of the male kind. 6.  The nominative case is that form or state of a noun or pronoun which usually denotes the subject of a finite verb.

Art is a verb. 1.  A verb is a word that signifies to be, to act, or to be acted upon.

Thou is a personal pronoun, of the second person, singular number, masculine gender, and nominative case. 1.  A pronoun is a word used in stead of a noun. 2.  A personal pronoun is a pronoun that shows, by its form, of what person it is. 3.  The second person is that which denotes the hearer, or the person addressed. 4.  The singular number is that which denotes but one. 5.  The masculine gender is that which denotes persons or animals of the male kind. 6.  The nominative case is that form or state of a noun or pronoun which usually denotes the subject of a finite verb.

That is a relative pronoun, of the second person, singular number, masculine gender, and nominative case. 1.  A pronoun is a word used in stead of a noun. 2.  A relative pronoun is a pronoun that represents an antecedent word or phrase, and connects different clauses of a sentence. 3.  The second person is that which denotes the hearer, or the person addressed. 4.  The singular number is that which denotes but one. 5.  The masculine gender is that which denotes persons or animals of the male kind. 6.  The nominative case is that form or state of a noun or pronoun, which usually denotes the subject of a finite verb.