Linguistics

• Proto-language, language that is the common ancestor of a set of related languages

Fiction

• Proto, one of the Nereids in Greek mythology
• Proto (Ghost in the Shell), fictional character in Masamune Shirow's Ghost in the Shell anime and manga

Others

• Silvio Proto, Belgian goalkeeper
• Proto, Christian martyr during the persecution of Valerian I
• Proto Malay, ethnic group in Malaysia
• Proto Motors, South Korean sports car manufacturer and refitter
• Siebe Gorman Proto, type of rebreather breathing set
• The PROTO tool company (formerly PLOMB), originally based in Los Angeles, California.
• Proto Matrix RAIL, paintball marker made by Dye under their brand Proto.
• Proto Matrix SLG, line of paintball markers made by Dye under their brand Proto.
• Proto Matrix M8, line of paintball markers made by Dye under their brand Proto.

See also

• Prototype (disambiguation)
• Proton
• Protein
• Protei