Admiral of the Fleet Terence Thornton Lewin, Baron Lewin, (19 November 1920 – 23 January 1999) was a Royal Navy officer. He served in the Second World War and then commanded a destroyer, the Royal yacht, two frigates and an aircraft carrier before achieving higher command in the Navy. He was First Sea Lord and Chief of the Naval Staff in the late 1970s and in that role he worked hard to secure a decent wage for servicemen and helped win them a 32% pay rise. He went on to be Chief of the Defence Staff during the Falklands War giving Prime Minister Margaret Thatcher his resolute support when losses began to be suffered. He was also the first Chief of Defence Staff to act as Head of the Armed Forces rather than just Chairman of the Chiefs of Staff Committee.