Peter Twinn, English mathematician and entomologist (d. 2004)

Peter Frank George Twinn (9 January 1916 – 29 October 2004) was a British mathematician, Second World War codebreaker and entomologist. The first professional mathematician to be recruited to GC&CS. Head of ISK from 1943, the unit responsible for decrypting over 100,000 Abwehr communications.