Units of area | Customary units in India | Obsolete units of measurement
A cawnie is an obsolete unit of land area used in Chennai (formerly Madras) in India. It was approximately equal to 1.322 acres. In SI units that is 5349 square metres. After metrication in the mid-20th century, the unit became obsolete. It is also known as Kani. 1 kani is equal to 17280 Square Feet. (Wikipedia).