stemming is the process during which a word reduces its affixes (suffixes, prefixes, etc.) and finally, the stem only remains. Stemming is used to detect related words with the same stem, the word root which does not change in any case, number or tense. The word stems are available in Portuguese corpus ptTenTen or Turkis corpus trTenTen. This analysis is processed with tools calle stemmers.
Stemming is also used instead of lemmatization with aglutinating langauges such as Hungarian or Turkish.