lemma

/'lemə/

Thân thiện

A student writes a lemma at the top of a page in their notebook.

Definition

1. Noun:
   • A heading or title: In academic or reference works, a lemma is the word or phrase that serves as the heading for an entry, annotation, or a section of a literary composition. It is the subject under discussion.
   • A botanical term: In botany, specifically in grasses (Gramineae), the lemma is the lower and typically stouter of the two bracts (glumes) that immediately enclose a floret.
   • A mathematical/logical proposition: In mathematics and logic, a lemma is a subsidiary or intermediate proposition that is assumed to be true and is used as a stepping stone in proving a larger, more significant theorem.

Usage Examples

• As a heading or title:

  • The dictionary lists each word as a lemma in bold type.
  • The lemma for this section of the commentary is clearly marked.

• As a botanical term:

  • The structure of the grass seed includes a palea and a lemma.
  • The lemma protects the developing floret.

• As a mathematical proposition:

  • The proof of the main theorem relied on a crucial lemma about prime numbers.
  • She first had to establish a supporting lemma before proceeding.

Advanced Usage

• In computational linguistics: In this field, a lemma is the canonical form, dictionary form, or base form of a set of words (e.g., "run" is the lemma for "runs", "ran", "running").
  • The software reduces all inflected forms of a verb to a single lemma for analysis.

Variants and Related Words

• Lemmas (n): The standard plural form.
• Lemmata (n): A less common, often scholarly plural form derived from Greek.
• Sublemma (n): A secondary or subordinate lemma listed under a main lemma in a reference work.

Synonyms

• Heading: A title at the head of a page or section.
• Bract: A modified leaf associated with a flower (related to the botanical sense).
• Proposition: A statement or assertion that expresses a judgment or opinion (related to the mathematical sense).
• Base form: The simplest form of a word (related to the linguistics sense).

Related Phrases

• "To state/prove a lemma": A common phrase in mathematical writing.
  • The author stopped to prove a necessary lemma.

Notes on Meaning

• The meaning of "lemma" is highly specialized and depends entirely on the academic or professional context (lexicography, botany, mathematics/logic, linguistics). It is not used in everyday conversation.

Học thuật

Noun

1. the heading that indicates the subject of an annotation or a literary composition or a dictionary entry
2. the lower and stouter of the two glumes immediately enclosing the floret in most Gramineae
3. a subsidiary proposition that is assumed to be true in order to prove another proposition

Từ đồng nghĩa

• flowering glume