In speech and writing the answer to whom (and what) is a noun or pronoun. For example: Whom did John Doe accuse? Answer: He accused Bill Smithers. What did Jane Doe eat?Answer: She ate sirloin steak followed by raspberries with cream.
The part of speech that answers "what" or "whom" in a sentence is a pronoun. Pronouns are words like "he," "she," "it," "they," "who," and "what" that replace nouns in a sentence.
"What" is a pronoun. It's the object form of "who", meaning that's used after prepostions ("to whom, by whom") and in formal speech as the direct object of verbs (whom should I tell?) "What" can be a pronoun, adjective, or adverb. In "What did you say?" it's a pronoun. In "what books have you read?" it's an adjective. In "what with one thing and another, this is hard" it's an adverb.
Give the letter to Mary. to whom?The letter is for Mary. for whom?
transactional speech is when someone answers a question and another person answers it
What is used for things. Whom is used for a person.
Pronoun
A noun that answers the question "To Whom?" ot "To What?" or "For Whom?" or "For What?"
"Answers what" refers to providing information or clarification about a topic or question, while "answers whom" refers to identifying the person or entity that is the subject of a question.
Proper nouns
The word "whom" is a pronoun. It is used as the object of a verb or preposition in a sentence.
an indirect object
Whom = ος / η / ο . Hope that answers your question.