Phrase guide

quadratic form

noun · 2 senses · updated from the 2026-07-25 local source snapshot

Definitions and examples are grouped by meaning. Pronunciation, history, word forms, translations, descendants, synonyms, antonyms, derived terms, and related words appear whenever the source provides them.

Sound

Pronunciation

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1

noun

Meaning 1

A homogeneous polynomial of degree 2 in a given number of variables.

Definition source: English Wiktionary via Wiktextract

Topics: algebra, mathematics, number-theory, sciences

Examples

  • 2004, Nikita A. Karpenko, Izhboldin's Results on Stably Birational of Equivalence Quadrics, Oleg T. Izhboldin, Geometric Methods in the Algebraic Theory of Quadratic Forms, Springer, Lecture Notes in Mathematics 1835, page 156, We claim that this quadratic form is isotropic, and this gives what we need according to [2, Proposition 4.4].
  • 2009, R. Parimala, V. Suresh, J.-P. Tignol, On the Pfister Number of Quadratic Forms, Ricardo Baeza, Quadratic Forms—Algebra, Arithmetic, and Geometry, American Mathematical Society, page 327, The generic quadratic form of even dimension n with trivial discriminant over an arbitrary field of characteristic different from 2 containing a square root of −1 can be written in the Witt ring as a sum of 2-fold Pfister forms using n − 2 terms and not less. The number of Pfister forms required to express a quadratic form of degree 6 with trivial discriminant is determined in various cases.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

2

noun

Meaning 2

A scalar quantity of the form εTΛε, where ε is a vector of n random variables, and Λ is an n-dimensional symmetric matrix.

Definition source: English Wiktionary via Wiktextract

Qualifier: multivariate statistics

Topics: mathematics, sciences, statistics

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

History

Etymology

No etymology was provided for this word.

Across languages

Translations

5 source translations are retained for this English entry.

  • Catalan: forma quadràtica — homogeneous polynomial of degree 2
  • Italian: forma quadratica — homogeneous polynomial of degree 2
  • Polish: forma kwadratowa — homogeneous polynomial of degree 2
  • Spanish: forma cuadrática — homogeneous polynomial of degree 2
  • Polish: forma kwadratowa — scalar quantity of form εTΛε