Tasmania has undergone several name changes since the Europeans discovered it.

However, prior to the first sighting by Europeans, the island had been inhabited only by the Aboriginal people for 35,000 years. The reconstructed Palawa kani language name for Tasmania is Lutriwita

Upon sighting land on 24 November 1642. Dutch explorer Abel Tasman named the island "Anthoonij van Diemenslandt" after his sponsor Anthony van Diemen, the Governor of the Dutch East Indies. The name was later shortened to Van Diemen's Land by the British. It was officially renamed Tasmania in honour of its first European's discovery and to remove the stigma of having been known as a harsh penal colony for 50 years.

Tasmania was sometimes referred to as "Dervon", as mentioned in the Jerilderie Letter written by the notorious Australian bushranger Ned Kelly in 1879. The colloquial expression for the state is "Tassie". Tasmania is also colloquially shortened to "Tas", especially when used in business names and website addresses. TAS is also the Australia Post abbreviation for the state.

More Info: en.wikipedia.org