Greek term for a course dealing with rules of language?

The Greek term for a course dealing with the rules of language is γραμματική (grammatike).

This term is directly derived from the Greek word "gramma" (γράμμα), meaning "letter" or "writing," which itself is related to the verb "graphein" (γράφειν), meaning "to write."

So, grammatíke literally means "the study of writing" or "the art of writing." However, its meaning has evolved to encompass the broader concept of language rules, including syntax, morphology, and semantics.