The pronoun 'who' is used as a subject pronoun.
The pronoun 'whom' is used as an object pronoun.
The pronouns 'who' and 'whom' are interrogative pronouns and relative pronouns.
An interrogative pronoun introduces a question.
A relative pronoun introduces a relative clause.
Examples:
Who is your new math teacher? (interrogative pronoun, subject of the sentence)
Mr. Smith who taught science is also teaching math. (relative pronoun, subject of the relative clause)
To whom should I give my completed application? (interrogative pronoun, object of the preposition 'to')
The manager is the one to whom you give the application. (relative pronoun, object of the preposition 'to')
Are you asking if this expression would be acceptable in formal English? It may not be the worst usage in formal English, but I would look for another way to say it. It is idiomatic, and may not give a consistent meaning to any reading expecting standard usage.
formal usage
formal usage
You can say "dda diolch" in Welsh to mean 'fine thank you'.
Our USA grammar originated from England's common usage grammar
The word whomever is a pronoun. It is the formal usage of whoever.
To whom it may concern;
To whom it may concern Who is a subject pronoun; it is used as the subject of a verb. Whom is an object pronoun. If you find you can replace who/whom with he, she, or they, who is correct. If you find you've replaced who/whom with him, her, or them, then whom is correct.
In classic usage, "semi-formal" implies a jacket for the man, though not a dinner jacket or tux jacket.
Words can shift from slang to formal or vice versa due to changes in society, culture, and generational preferences. Slang terms may become formalized as they gain widespread acceptance, while formal words can become slang through informal usage among specific social groups or through popular media influence. Additionally, language evolution, technological advancements, and global trends can also impact the transformation of words between slang and formal language.
Do you expect me to eat this glop? Note that "glop" is informal usage and would not be used in formal writing.
'to whom it may concern' too formal?