A dictionary service such as WordNet [1] offers definitions for words. This goes back to Aristotle's emphasis on definitions. We have since learnt that we cannot reduce a language to the definition of all its terms. There is always more to it: Culture, innuendo, etc.

In restricted environments, however, a dictionary still works. For non-English speakers on IRC, for example, bots that query WordNet are often useful. FOAF uses this as well; see Foaf:WhyWordnetIsCool.

This is easily extended for things where most people share the same intentions: Names of people, events, and places. For example: "RDFWeb apps have used Wordnet to exploit a large RDF taxonomy of noun terms. TAP adds to this by providing TAP identifiers for specific things, such as people, places, etc." [2]

Note that a dictionary service just works like a dictionary; it maps terms to definitions. A LinkLanguage maps terms to explanations, opinions, and discussion. A PatternLanguage maps terms to pattern descriptions, and patterns are particular solutions to particular problems.