Physicist. Born in Brechin, a remote descendant of engineer James Watt (1736 - 1819), Watson-Watt was educated at University College, Dundee, then part of the University of St Andrews. Watson-Watt worked initially for the Meteorological Office designing devices to locate thunderstorms. He also coined the term 'Ionosphere' to describe an atmospheric layer.
He developed this work in terms of radio-detection while at the National Physical Laboratory in the 1930s. He became an advisor to the Air Ministry during World War II and developed and introduced Radio Detection And Ranging (RADAR) technology to track enemy aircraft. In recognition of the important role played by RADAR in defending Britain against German air raids, he was knighted in 1942.
His first marriage was dissolved in 1952 and, in 1966, he married Dame Kathryn Trefusis-Forbes who was the first Director of the Women's Air Auxiliary Force, and the niece of scientist Prof. George Forbes (1849 - 1936).
Watson-Watt died in Inverness and lies buried the churchyard of Holy Trinity Scottish Episcopal Church in Pitlochry.