Tahiti is the largest island in the Windward group of French Polynesia, located in the archipelago of Society Islands in the southern Pacific Ocean.

The island has a population of 178,133 according to an August 2007 census. This makes it the most populous island of French Polynesia, accounting for 68.6% of the total population. The capital, Papeete, is located on the northwest coast. Tahiti has also been known as O'tahiti.

Tahiti measures 45 km (27.96 mi) across at its widest point and covers an area of 1,045 km2 , with a maximum elevation of 2,241 m (Mount Orohena). Mont Roonui in the southeast rises to 1,332 m. The island consists of two roughly round portions centered on volcanic mountains, connected by a short isthmus named after the small town of Taravao located there. The northwestern portion is known as Tahiti Nui ("big Tahiti"), while the much smaller southeastern portion is known as Tahiti Iti ("small Tahiti") or Taiarapu. Tahiti Nui is heavily populated along the coast (especially around Papeete) and benefits from roads and highways.