Why do some Turkish words have double letters, like "göz"?

One of the distinctive features of the Turkish language is the use of double letters in some words. Double letters are created by adding two letters with the same sound to make it longer. It serves various purposes, such as to distinguish the meaning of homophones, to indicate sound length, or to add emphasis to a word.

For instance, the word "göz" in Turkish means "eye." Without the double letter "z," the word "goz" would mean "a kind of furniture with drawers." Another example is the word "kötü" which means "bad." In contrast, the word "kotu" without the double letter "ö" has no meaning in Turkish dictionary.

The use of double letters in Turkish follows specific spelling and grammar rules, and it is important for Turkish learners to understand these rules. Usually, the double vowels stem from suffixes, and there are guidelines for when to use them. One general rule is that a double letter ends a short syllable if one of the letters is the vowel /e/ or /ı/ and ends a long syllable if one of the letters is the vowel /a/ or /o/.