Arthur David Jacobs (14 June 1922 – 13 December 1996) was an English musicologist, music critic, teacher, librettist and translator. Among his many books, two of the best known are his Penguin Dictionary of Music, which was reprinted in several editions between 1958 and 1996, and his biography of Arthur Sullivan, which was praised by critics in Britain and America. He was a music critic at newspapers from 1947 to 1975, an editor at Opera magazine from 1961 to 1971, and served on Opera's editorial board from 1971 until his death. He was also a frequent contributor to The Musical Times for five decades. Jacobs taught at the Royal Academy of Music, at Huddersfield Polytechnic, and at universities in the US, Canada, and Australia from 1964 to 1985 and translated more than 20 operas into English.