This page gives a glossary of the most important terms in the search engine nomenclature.

A

• Analyzer: Analyzers are components that preprocess input text at index time and/or at search time. It's important to use the same or similar analyzers that process text in a compatible manner at index and query time. For example, if an indexing analyzer lowercases words, then the query analyzer should do the same to enable finding the indexed words.

F

• Full text search:

• Free text:

P

• Protected word: A word that is not modified by any stemming transformation.

S

• Stemming: A transforming algorithm that reduces any of the forms of a word such as "runs, running, ran" to its elemental root ("run") or that does the inverse, that is, it takes a root word and expands it to all of its various form.

• Stop word:

T

• Token: An analyzer splits up an input text into a series of tokens. A token is a substring of the input text that is indexed or queried for and not split any further.