United States

Tree of Life Web Project

"The Tree of Life Web Project is a collection of information about biodiversity compiled collaboratively by hundreds of expert and amateur contributors. Its goal is to contain a page with pictures, text, and other information for every species and for each group of organisms, living or extinct. Connections between Tree of Life web pages follow phylogenetic branching patterns between groups of organisms, so visitors can browse the hierarchy of life and learn about phylogeny and evolution as well as the characteristics of individual groups."

Herb Thesaurus

"This thesaurus functions as a means for indexing articles, photos, and web pages on some of the basic identifying characteristics of herbs. It is designed for the hobbyist or recreational gardener rather than scientist or medical reference. The preferred terminology is that of a home gardener rather than a herbalists or botanists since they are the targeted end-user. (...) This mini-thesaurus contains preferred terms selected based on common usage, and the cross-references are made from the non-preferred terms. Scope notes have been added where necessary.

Medical Subject Headings

"MeSH is the National Library of Medicine's controlled vocabulary thesaurus. It consists of sets of terms naming descriptors in a hierarchical structure that permits searching at various levels of specificity. MeSH descriptors are arranged in both an alphabetic and a hierarchical structure. At the most general level of the hierarchical structure are very broad headings such as 'Anatomy' or 'Mental Disorders'. More specific headings are found at more narrow levels of the twelve-level hierarchy, such as 'Ankle' and 'Conduct Disorder'. There are 26,142 descriptors in 2011 MeSH.

Alexandria Digital Library Feature Type Thesaurus

"The Feature Type Thesaurus contains a hierarchical scheme of terms for typing gazetteer entries; that is, for typing named geographic places. It is intended for general use for many types of gazetteers and as a shared vocabulary for interoperability among gazetteers. It has been designed to be used with the Alexandria Digital Library (ADL) Gazetteer."

NASA Thesaurus

"The Hierarchical Listing With Definitions contains all subject terms and USE cross references currently approved for use, and displays the full hierarchical structure for each term along with a definition when available. In addition, the listing has been developed to serve as an orthographic authority for upper/lowercase forms of all terms and cross references. The term-added date, displayed for all terms added after April 1988, is also given.