New Grove Dictionary of Music and Musicians
Music Reference Shelf under call number ML100 .N48 2001
The New Grove, second edition, includes entries on persons and subjects. While predominantly a classical music resource, it now includes jazz, popular, and world music. Also available electronically as Grove Music Online, which is part of Oxford Music Online. The landing page will say Oxford Music Online, but you will be searching Grove:
Grove Music Online
The electronic version of the New Grove Dictionary of Music and Musicians incorporates the New Grove Dictionary of Opera and the New Grove Dictionary of Jazz.
Die Musik in Geschichte und Gegenwart
comprehensive music encyclopedia in German
Music Reference Shelf under call number ML100 .M92 1994
This second edition is divided into two sections, the Sachteil (terms) and Personenteil (people). The 1994 in the call number was the date the first volume was issued, but the rest of the encyclopedia was issued piecemeal and was finally completed in 2007.
authoritative dictionary of musical terms; available electronically through Credo Reference
Music Reference Shelf under call number ML 100 .H37 2003
Please note: the original edition, which came out in 1944 (ML 100 .A64, also on Music Reference Shelf) was called the Harvard Dictionary of Music. The author was renowned musicologist Willi Apel. It was updated several times (for example, ML100 .A64 1969, also on Music Reference Shelf). The new edition of 1986 (ML100 .N485 1986, also on Music Reference Shelf) was renamed the New Harvard Dictionary of Music. The latest edition which came out in 2003, however, is once again called the Harvard Dictionary of Music.
The following are all available as online databases from Credo Reference: