Sentence:  Text <WSD>corpora</WSD> are being used in most current lexicographic projects. Applied linguistic research is another field where text <WSD>corpora</WSD> are welcome as an inexhaustible source of empirical information, a polygon for testing various linguistic tools – spell-checkers, OCRs, machine translation systems, NLP systems, etc. 
Meaning of the word marked with <WSD> tags:  Such a collection in form of an electronic database used for linguistic analyses.