Thera is a diminutive form of the name Theresia, which is of Greek origin. The name Theresia itself is derived from the Greek word 'therizo,' meaning 'to harvest.' Thera is also the ancient name for the island of Santorini, which is part of the Cyclades group in the Aegean Sea. The island is historically significant due to its volcanic activity, particularly the massive eruption around 3,600 years ago that shaped its current landscape.