Etymology is one of the main fields of philology. Researching the etymology of Turkish words has been one of the challenging fields of philology, since Turkish has spread to different geographic areas and has been in contact with different languages throughout its long history. It is not easy to analyze the etymology of the Turkish word diachronically. In order to overcome this difficulty, it need to make use of the branches of Turkish that are spread over different areas. The comparative Turkic languages method is the name of the method to be used to overcome this difficulty. It is much more difficult to find the origin of Old Turkic words than to find the origin of words in other periods of Turkish language. The way to make correct etymological research in Old Turkic is through a fit analysis of formation in words. One of the words with ambigous about its formation is ulu?. In the article, the previous explanation about the structure of the word was evaluated and a new proposal was proposed.
Old Turkic, etymology, ul, ula-, ulu?.