Kinship and family

kardeş (noun): a brother or sister, someone born of the same mother or father. The older form is karındaş. It is built from karın 'belly, womb' and the suffix -daş, which marks sharing, so the word literally means 'one of the same womb'. TDK and the etymological dictionaries agree on this. As surnames, Kardeş and its plural Kardeşler are among the plainest cases of a kinship word becoming a family name.

From form of address to register entry

Before 1934 most people had no official family name. They were known by their father's name, by a nickname, or through a relative: 'the maternal uncle's son', 'the paternal uncle's son'. When the Surname Law (Law No. 2525) took effect, some of these everyday labels went into the register. Article 6 of the Surname Regulation says a surname is used either alone or together with “(oğlu)”. So it is no surprise that kinship words so often appear with -oğlu.

Three patterns stand out:

• Bare word: Ata, Kardeş, Yeğen, Torun, Bacı.
• Word + -oğlu: Babaoğlu, Dayıoğlu, Emmioğlu.
• Compound or plural: Babacan (baba + can), Kardeşler (kardeş + plural -ler).

The examples, word by word

Ata has meant 'father; forefather' since Old Turkic. In names such as Atay and Atalay, ata works as a name element instead, and those belong to another category.

Babaoğlu is 'the father's son'. Baba is an old nursery word in Turkish, with look-alikes in many unrelated languages.

Dayıoğlu rests on dayı, a mother's brother. Turkish keeps separate words for the two kinds of uncle, and dayı is the Turkic word for the maternal side.

Emmioğlu means 'son of the paternal uncle'. Emmi is the dialect form going back to Arabic ʿamm 'paternal uncle'; standard Turkish says amca.

Babacan joins baba with can 'soul, life', a Persian loan. As an ordinary adjective, babacan also describes a warm, protective, fatherly person.

Yeğen is a nephew or niece, and the word is Turkic. Torun is a grandchild, also Turkic. Bacı means an elder sister, or simply a sister.

Why the group is worth a look

Kinship names look inward. An occupation ties a family to the market, a place name ties it to a town; Dayıoğlu defines a family through another relative. That is the voice of everyday speech from before surnames existed. Still, saying that a particular family was once known this way needs a document. The meaning of the word does not, by itself, tell the family's story.

One related case: Atatürk also contains ata, but it was conferred by a separate law, Law No. 2587. It is therefore treated with the homeland and nation words, not here.