Morys George Lyndhurst Bruce, 4th Baron Aberdare (16 June 1919–23 January 2005) was a Conservative politician, and from 1999 until his death one of ninety elected hereditary peers in the British House of Lords.

In 1932, Bruce began his education at Winchester College in Hampshire, and four years later, he matriculated at New College, Oxford. He then joined the British Army, commissioned with the rank of Lieutenant in the Welsh Guards; he would eventually reach the rank of Captain, after having served in various staff positions with XII Corps , the 21st Army Group, and XXX Corps during and after World War II.

He joined the Arthur J. Rank Organisation in 1947, working there for two years before moving to the British Broadcasting Corporation, where he worked between 1949 and 1956. In 1970, he became Minister of State for the Department of Health and Social Security; in 1974, he was appointed to the Privy Council and became a Minister without Portfolio. Between 1976 and 1992, he served as Chairman of the Committees of the House of Lords , (Deputy Speaker of the House of Lords). In 1984, he was created a Knight Commander of Order of the British Empire, and he would serve various positions within the Order of St John of Jerusalem. After the House of Lords Act 1999 prevented hereditary peers from sitting on the Lords solely by virtue of their peerages, Lord Aberdare became one of the ninety hereditary peers elected to stay in the House of Lords.