Thesauri: Services and Other Resources (Library of Congress): "

Subject cataloging depends on lists of controlled subject access vocabulary and thesauri. Library of Congress catalog records generally feature subject access points from one or more of the following thesauri and headings lists:

Library of Congress Subject Headings is available in print and electronic form from the Library of Congress Cataloging Distribution Service. Subject headings created each week since the most recent full edition are available on the Library of Congress Cataloging Policy and Support Office Web page and in the Cataloging Service Bulletin, on subscription from the Cataloging Distribution Service.

Binding Terms: A Thesaurus for Use in Rare Book and Special Collections Cataloguing (Chicago: Association of College and Reseach Libraries, ALA)
Global Legal Information Network (GLIN) Thesaurus. (Washington, DC: Law Library of Congress) ...

Links to Online Thesauri:

Thesaurus for Graphic
Materials I: Subject Terms

Thesaurus for Graphic
Materials II: Genre and Physical Characteristic Terms

Moving Image
Genre-Form Guide

GLIN Thesaurus

Legislative Indexing
Vocabulary