Shah (Persian: شاه) is a Persian word which means the king or ruler of a country. This word is used in different countries in the world, including Iran, India, Pakistan and Afghanistan. Presently the term "Shah" is used as a surname commonly by many people in India, Pakistan and Afghanistan who are Hindu, Muslim and Jain. Many Indian names which have Shah in them; the most famous of them is Shah Jahan, who as the Emperor of India ordered the creation of Taj Mahal. One possible etymology of the chess term checkmate is the Persian shah mat, meaning "the king cannot escape"
The term "Shah" often means Mohammad Reza Pahlavi, Shah of Iran from 1949 to 1979.