Kutub al-Lughah is a work of Hebrew

Hebrew language

Hebrew is a Semitic language of the Afroasiatic language family. Culturally, is it considered by Jews and other religious groups as the language of the Jewish people, though other Jewish languages had originated among diaspora Jews, and the Hebrew language is also used by non-Jewish groups, such...

 linguistics

Linguistics

Linguistics is the scientific study of human language. Linguistics can be broadly broken into three categories or subfields of study: language form, language meaning, and language in context....

 by Saadia Gaon

Saadia Gaon

Saʻadiah ben Yosef Gaon was a prominent rabbi, Jewish philosopher, and exegete of the Geonic period.The first important rabbinic figure to write extensively in Arabic, he is considered the founder of Judeo-Arabic literature...

, twelve "Books on Language" which are also designated as the twelve parts of a work entitled "The Book on Language", in which, as the author himself states in his "Sefer ha-Galui", he sought to explain the "i'rab", or the grammatical formation of the Hebrew language. Of this Hebrew grammar, which is the oldest one known, fragments of greater or less extent have been preserved, especially in Saadia's commentary on the "Sefer Yeẓirah" and by Dunash ben Labrat

Dunash ben Labrat

Dunash ha-Levi ben Labrat was a medieval Jewish commentator, poet, and grammarian of the Golden age of Jewish culture in Spain. He was, according to Moses ibn Ezra, born in Fes. In his youth he travelled to Bagdad to study with Saadia Gaon.Dunash is called the founder of Spanish Hebrew poetry...

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