A word that is included in a glossary or list of headwords; a headword.

The set of different forms of a word, such as the inflected forms of a verb, e.g., 'sing', 'sings', 'sang', 'sung', 'singing' are one lemma, 'boy', 'boys' another.

a canonical form taken as the representative for all the different forms of a paradigm

a dictionary head-word, which is realized by various word-forms

lower case ASCII text of word as found in the WordNet database index files.

It is the group of all inflected forms of a word. For example, the lemma of all the forms of a verb is the infinitive (e.g., "be" for "is", "were", or "was"). The lemma of a plural is the singular (e.g., "foot" for "feet", or "protein" for "proteins").

the headword or citation form of an inflected word, especially the form found in a bilingual dictionary. This is usually, for verbs: the infinitive or the present tense, first person singular; and for nouns: the nominitive singular. (In linguistics the word is sometimes used in a sense which includes this definition plus all the inflections cf lexeme).

In linguistics, and particularly in morphology, a lemma or citation form is the canonical form of a lexeme. Lexeme refers to the set of all the forms that have the same meaning, and lemma refers to the particular form that is chosen by convention to represent the lexeme. Lemmas have special significance in highly inflected languages such as Czech.