A person who deals with or treats any immaterial thing, spec. one who discusses a subject in speech or writing; a person who treats someone or…

One who treats of or writes upon a subject.

The writer of a treatise.

One who treats of a subject; the writer of a tractate.

One who writes an ‘exercitation’.

One who writes or utters a diatribe; †the writer of a critical dissertation.

One who makes a dissertation.

A writer, publisher, or distributor of tracts. nonce-uses.

The writer of a tract or treatise. tracˈtitious adj. rare (see quot.).

The author of a disquisition.

one who makes a dissertation.

One who makes disquisition; an inquirer or investigator; the author of a disquisition.