tank [E17th] In early 17th-century English, tank was the name given to a pool in India, going back to Sanskrit tadāga ‘pond’ probably also influenced by the Portuguese word for ‘pond’, tangue. It was being used for a domestic container of liquid in the modern way by the end of the 17th century. In 1915 tank was used as a secret code word for the armoured military vehicles that were first being developed. A Times column of September 1916 remarked: ‘The name has the evident official advantage of being quite undescriptive.’ A sleeveless tank top is so called not because it was worn by the driver of a tank but because it resembles the top part of a one-piece swimsuit known as a tank suit, worn in ‘swimming tanks’ or swimming pools. A drunk person has been tanked up since the 1890s. The comparison is with a tank filled with liquid.