Cross-language information retrieval (CLIR) is a subfield of information retrieval dealing with retrieving information written in a language different from the language of the user's query. For example, a user may pose their query in English but retrieve relevant documents written in French. To do so, most of CLIR systems use translation techniques.[2] CLIR techniques can be classified into different categories based on different translation resources:

  • Dictionary-based CLIR techniques
  • Parallel corpora based CLIR techniques
  • Comparable corpora based CLIR techniques
  • Machine translator based CLIR techniques

The first workshop on CLIR was held in Zürich during the SIGIR-96 conference. Workshops have been held yearly since 2000 at the meetings of the Cross Language Evaluation Forum (CLEF).

The term "cross-language information retrieval" has many synonyms, of which the following are perhaps the most frequent: cross-lingual information retrieval, translingual information retrieval, multilingual information retrieval. The term "multilingual information retrieval" refers to CLIR in general, but it also has a specific meaning of cross-language information retrieval where a document collection is multilingual.

Google Search had a cross-language search feature that was removed in 2013.[3]

  • EXCLAIM (EXtensible Cross-Linguistic Automatic Information Machine)