Why Telugu is called Telugu?

Telugu is the language spoken by 80 million andhrites.. but does any one knows what telugu means??
The etymology of the word Telugu is not known for certain.
It is explained as being derived from trilinga, as in Trilinga Desa, "the country of the three lingas". According to a Hindu legend, Trilinga Desa is the land in between three Shiva temples namely Srikalahasti, Srisaila and Draksharama. Trilinga Desa forms the traditional boundaries of the Telugu region. Other forms of the word, such as Telunga, Telinga, and Tenunga were also seen.