Standard Lemma guide
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
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noun
A range; a continuous, infinite, one-dimensional set, possibly bounded by extremes.
Definition source: English Wiktionary via Wiktextract
Synonyms: sliding scale, continuum
Antonyms: none provided
noun
Specifically, a range of colours representing light (electromagnetic radiation) of contiguous frequencies; hence electromagnetic spectrum, visible spectrum, ultraviolet spectrum, etc.
Definition source: English Wiktionary via Wiktextract
No example sentence was provided for this meaning.
Synonyms: none provided
Antonyms: none provided
noun
The autism spectrum.
Definition source: English Wiktionary via Wiktextract
Usage: usually
Topics: education, human-sciences, psychology, sciences
No example sentence was provided for this meaning.
Synonyms: none provided
Antonyms: none provided
noun
A set of frequencies that are used for radio-frequency communication; not necessarily a continuous range.
Definition source: English Wiktionary via Wiktextract
Topics: communications, electrical-engineering, engineering, natural-sciences, physical-sciences, telecommunications
No example sentence was provided for this meaning.
Synonyms: none provided
Antonyms: none provided
noun
The pattern of absorption or emission of radiation produced by a substance when subjected to energy (radiation, heat, electricity, etc.).
Definition source: English Wiktionary via Wiktextract
Topics: chemistry, natural-sciences, physical-sciences
No example sentence was provided for this meaning.
Synonyms: none provided
Antonyms: none provided
noun
The set of eigenvalues of a matrix.
Definition source: English Wiktionary via Wiktextract
Topics: linear-algebra, mathematics, sciences
No example sentence was provided for this meaning.
Synonyms: eigenspectrum
Antonyms: none provided
noun
Of a bounded linear operator A, the set of scalar values λ such that the operator A—λI, where I denotes the identity operator, does not have a bounded inverse; intended as a generalisation of the linear algebra sense.
Definition source: English Wiktionary via Wiktextract
Qualifier: functional analysis
Topics: mathematics, sciences
No example sentence was provided for this meaning.
Synonyms: none provided
Antonyms: none provided
noun
An abstract object in mathematics created from a commutative ring R and denoted operatorname Spec(R) or operatorname SpecR and said to be the spectrum of R; useful in the study of such rings for providing a geometric object which encodes many of the properties R, and in modern geometry for generalizing the notion of an algebraic variety to that of an affine scheme. Formally, the set of all prime ideals R equipped with the Zariski topology and augmented with a sheaf of rings called the structure sheaf, generated by the B-sheaf on the distinguished open sets D_f which assigns the localization of R at f to each set D_f, regarded as a ring of functions on D_f. See Spectrum of a ring on Wikipedia.Wikipedia
Definition source: English Wiktionary via Wiktextract
Qualifier: commutative algebra
Topics: algebraic-geometry, geometry, mathematics, sciences
No example sentence was provided for this meaning.
Synonyms: none provided
Antonyms: none provided
Broader terms: scheme
Narrower terms: Stone space
noun
Specter, apparition.
Definition source: English Wiktionary via Wiktextract
Usage: obsolete
No example sentence was provided for this meaning.
Synonyms: none provided
Antonyms: none provided
noun
The image of something seen that persists after the eyes are closed.
Definition source: English Wiktionary via Wiktextract
No example sentence was provided for this meaning.
Synonyms: none provided
Antonyms: none provided
noun
a broad range of related objects or values or qualities or ideas or activities
Definition source: Princeton WordNet 3.0
No example sentence was provided for this meaning.
Synonyms: none provided
Antonyms: none provided
Broader terms: scope, range, reach, orbit, compass, ambit
noun
an ordered array of the components of an emission or wave
Definition source: Princeton WordNet 3.0
No example sentence was provided for this meaning.
Synonyms: none provided
Antonyms: none provided
Broader terms: array
Narrower terms: absorption spectrum, action spectrum, atomic spectrum, electromagnetic spectrum, emission spectrum, infrared spectrum, line spectrum, mass spectrum, microwave spectrum, radio spectrum, radio-frequency spectrum, sound spectrum, acoustic spectrum, ultraviolet spectrum, visible spectrum, color spectrum
History
Etymology tree Proto-Indo-European *speḱ- Proto-Indo-European *-yeti Proto-Indo-European *spéḱyeti Proto-Italic *spekjō Latin speciō Proto-Indo-European *-tḗr Proto-Indo-European *-trom Proto-Italic *-trom Latin -trum Latin spectrumbor. English spectrum From Latin spectrum (“appearance, image, apparition”), from speciō (“look at, view”). Doublet of specter. See also scope.
Across languages
116 source translations are retained for this English entry.
