K-T-B is a triconsonantal root of a number of Semitic words, typically those having to do with writing. The words for "office", "writer" and "record" all reflect this root. Most notably, the Arabic word kitab ("book") is also used in a number of Semitic and Indo-Iranian languages, as well as Turkish. One cultural example would be the Mishnaic expression Katuv or the cognate Arabic expression transliterated as Maktoub, which may be translated as "it is written". Another would be the Koutoubia mosque of Marrakech, whose name is taken from the librarians and booksellers who once occupied that area.

Arabic derivatives

A full account of derivatives could be extensive, but some of them are these:

Hebrew derivatives

The same root is present in Hebrew: The Hebrew fricatives transcribed as "ḵ" and "ḇ" can also be transcribed in a number of other ways, such as "ch" and "v", which are pronounced and, respectively. They are transliterated "ḵ" and "ḇ" on this page to retain the connection with the pure consonantal root k-t-b. Also in Modern Hebrew, there is no gemination. In Hebrew, the root is used with the meaning of 'writing' but not for the noun for 'book', which is sefer. To a lesser extent in Hebrew, the word "Katuv" as a noun refers to the Tanakh.

Contrastive Arabic–Hebrew

A contrastive presentation of part of this can be as follows:

Other languages

In Maltese, the same root is present, and commonly used, similar to that in Arabic and Hebrew, such as ktibt (I wrote), ktieb (a book), kitba (writing), and kittieb (m. writer) amongst many more. In modern Tigrinya and Amharic, this root survives only in the noun kitab, meaning "amulet", and the verb "to vaccinate", it used to be used widely but it is now seen as an Archaic form. Ethiopic-derived languages like these usually use a different root (ṣ-ḥ-f) ص-ح-ف for the verb "to write" (this root exists in Arabic and is used to form words with a close meaning to "writing", such as ṣaḥāfa "journalism", and ṣaḥīfa "newspaper" or "parchment"). In the Persian language family (Farsi, Dari, Tajik, etc.) the borrowed word kitab is the most commonly used word for "book". This word has also made its way into the Malay language as "kitab", and into Swahili as "kitabu", both meaning book.