Language Packs

Language Packs are designed for software developers to extend the performance of their dtSearch Engine powered applications

Language packs include:

Stemming rules and noise-word files

dtSearch products are supplied with stemming rules and a noise-word file for English(US). Stemming is the only search expansion option which is ‘on’ by default in the dtSearch end-user products; the reason for this is that stemming is almost always useful when making a search, and adds little to the time required to make a search.

Unlike some other search engines, dtSearch applies stemming at search time, there is no need to build indexes specifically to apply stemming and no need to build separate indexes for each language in use.

The problem

The dtSearch English stemmer will find plurals and many other word variations; for example a search on print will also find prints, printers, printing, printed, printable. However, if you are searching documents written in other languages, the English stemming rules will cause you to miss many word variations which do not occur in English (e.g. verb and noun changes with gender), and words which are unrelated may be found in error.

In addition, the English noise word list, which is designed to remove unwanted English words from your index to keep the index size small, is not suitable for other languages; your indexes may contain many foreign words which will not be useful in searches and will add to the size of your indexes. The common English noise word the will stop you from getting results if you were searching French documents for tea!

The solution

Use language specific files in place of the default US English files. Language Extension Packs contain files for many languages in Unicode format, see list of supported languages

* User Thesaurus Plus can be licensed separately for use with the Site Search ONE WordPress Plugin.


Following a licensing agreement between dtSearch UK and dtSearch Corp,  dtSearch version 2022.02 (released 2 December 2022) and later include  stemming and noise word files for over 25 languages.

List Analyzer and Stemming Tester which were part of the Language Extension Packs are now on GitHub: