The technique of using a thesaurus, that is, a description of the morphology of words, in indexing text. It has to know both the rules of morphology for a language and the exceptions, so this is not a trivial task. Not the inflected forms of words are used, but only the stem; hence the name.

Everything 2 could make good use of this technique to reduce the duplication in titles. (The same technique can be used to support a multi-lingual Everything.)

The Dutch word stemming (German Stimmung) means tuning and mood.