Which root word signifies "written"?

The root word "gram-" comes from the Greek "gramma," which means "something written" or "a letter." This root is commonly found in various English words related to writing or recording, such as "grammar" (the system of a language's structure), "telegram" (a message sent by telegraph), and "graph" (a representation of data). The emphasis on the notion of writing or something that is written makes "gram-" the correct choice.

In contrast, the other root words have different meanings. "Raph-" relates to sewing or stitching, as seen in "raphy." "Hydro-" pertains to water, while "gen-" is associated with producing or generating, as in "generation" or "genetics." Understanding these distinctions highlights the unique connotation of "gram-" as it specifically denotes the idea of writing.