Koca-

The surname Kocabıyık describes a face: a big, bushy moustache. Kocabaş describes a big head. In such names koca is an adjective stressing size.

The TDK dictionary gives koca several senses. As an adjective it means ‘big, large’ and ‘old’. As a noun it means ‘husband’. Surnames mostly draw on the adjective. The step from ‘big’ to ‘old, elder’ is a natural one: the older person is the respected one.

Koca is a two-syllable word ending in a vowel, and vowel harmony does not change it. The element that follows keeps its own form. In Kocatürk back-vowel koca joins front-vowel Türk. The compound is written as one word, and the core meaning lies in the second element.

The examples fall into two groups. In one, koca qualifies a landscape word: Kocadağ is ‘big mountain’ and Kocakaya ‘big rock’. In the other, it describes a person. Kocabaş means ‘big head’ and Kocabıyık ‘big moustache’. Names like these may go back to nicknames. A nickname describes an appearance. It does not show that the people who carry the surname look that way. Kocaer combines koca with er ‘man, brave warrior’. Kocatürk reads as ‘great Turk’.

Kocaoğlu has a different structure. Here Koca is a nickname or a name, and the surname means ‘son of Koca’. Because koca ends in a vowel, -oğlu attaches directly with no linking sound. The form alone does not tell us whether the nickname meant ‘big’, ‘old’ or ‘great’.

Two forms invite a wrong split. Kocaman is a single word in the TDK dictionary, meaning ‘huge’. It is historically koca plus the suffix -man, but as a surname it is read as a plain word. Kocaeli is the name of a province. When it appears as a surname, that proper name comes first. Analysing it afresh as ‘koca + eli’ would mislead.

Koca- is among the best-known surname elements for size and age. It works in the same field as Ulu- and Büyük-.