The wat is the Siamese unique building. It replaces the university. Compared to the university, it has no prerequisite buildings, has an additional scientist slot and it provides +3 culture, but is does not provide extra science for worked jungle tiles.
Historical Info:
A "Wat" is a Buddhist monastery temple found in Cambodia, Thailand, or Laos. The literal translation of "wat" is "school", and indeed the Siamese wats were both places of worship and of learning. A wat consists of a temple containing statues of the Buddha, a prayer room, a room containing religious texts, a pavilion for relaxation, a library, study hall, bell towers, and living quarters. It may be a single building or a collection of structures- a town in itself. Constructed in the 12th century, the Angkor Wat in Angkor, Cambodia, is one of the largest and best- preserved wats in Southeast Asia.