verb (used with object), lem·ma·tized, lem·ma·tiz·ing.
  1. to sort (the words in a list or text) in order to determine the headword, under which other words are then listed.
Also especially British, lem·ma·tise.

Origin of lemmatize

1965–70; < Greek lēmmat- (stem of lêmma; see lemma1) + -ize
Related formslem·ma·ti·za·tion, noun
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for lemmatize



  1. (tr) linguistics to group together the inflected forms of (a word) for analysis as a single item
Derived Formslemmatization or lemmatisation, noun
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