What is "thematic catalogue"

Thematic \The*mat"ic\, a. [Gr. ?: cf. F. th['e]matique.]

1. (Gram.) Of or pertaining to the theme of a word. See Theme, n., 4.

2. (Mus.) Of or pertaining to a theme, or subject.

   Thematic catalogue (Mus.), a catalogue of musical works which, besides the title and other particulars, gives in notes the theme, or first few measures, of the whole work or of its several movements.

A thematic catalogue is an index used to identify musical compositions through the citation of either the opening notes (incipit) or main theme of the work. Such catalogues can be used for many purposes, including as guides to a specific composer's works, as an inventory of a library's holding or as an advertisement of a publisher's output. In addition to the musical identification, a thematic catalogue may continue information such as dates of composition and first performance. Works within a thematic catalogue can be grouped chronologically or by genre.

Thematic catalogues produced as scholarly guides to the works of a particular composer provide a shorthand means of identification for their music. The Bach-Werke-Verzeichnis (BWV) numbering system used for the works of Johann Sebastian Bach is one example.