View source for Spectrum

==English==
[[File:Spectrum-sRGB-low.svg|right|thumb|The visible spectrum]]
{{wikipedia}}

===Etymology===
{{root|en|ine-pro|*speḱ-|*-trom}}
From {{bor|en|la|spectrum||appearance, image, apparition}}, from {{m|la|speciō||look at, view}}. {{doublet|en|specter}}. See also {{m|en|scope}}.

===Pronunciation===
* {{IPA|en|/ˈspɛktɹəm/|a=GA,Canada,UK}}
* {{audio|en|LL-Q1860 (eng)-Vealhurl-spectrum.wav|a=Southern England}}
* {{audio|en|en-us-spectrum.ogg|a=Mid-Atlantic US}}
* {{rhymes|en|ɛktɹəm|s=2}}

===Noun===
{{en-noun|spectra|s}}

# A [[range]]; a [[continuous]], [[infinite]], [[one-dimensional]] set, possibly bounded by [[extremes]].
#: {{nearsyn|en|sliding scale}}
#* {{quote-journal|en|date=November 7, 2012|author=Matt Bai|title=Winning a Second Term, Obama Will Confront Familiar Headwinds|work=New York Times|url=http://www.nytimes.com/2012/11/07/us/politics/in-president-obamas-second-term-familiar-challenges.html?pagewanted=all&_r=0
|passage=As Mr. Obama prepared to take the oath, his approval rating touched a remarkable 70 percent in some polling — a reflection of good will across the political '''spectrum'''.}}
# Specifically, a range of [[colour]]s representing [[light]] ([[electromagnetic radiation]]) of contiguous [[frequency|frequencies]]; hence [[electromagnetic spectrum]], [[visible spectrum]], [[ultraviolet]] spectrum, etc. {{defdate|from later 17th c.}}
#* {{quote-journal|en|date=October 30 2010|author=Jim Giles|title=Jammed!|journal=w:New Scientist
|passage=Current 3G technologies can send roughly 1 bit of data - a one or a zero - per second over each 1 Hz of '''spectrum''' that the operator owns.}}
# {{lb|en|psychology|education|usually with '''the'''}} The [[autism spectrum]].
#* {{quote-book|en|year=2022|author=[[w:Percival Everett|Percival Everett]]|title=Dr. No|publisher=Influx Press (2023)|page=110|passage=He punctuated his words with a look into my eyes that might have been read as threatening or menacing by anyone who was not on the '''spectrum'''. But I am on the '''spectrum''', and so I stared back at him.}}
# (''[[chemistry]]'') The pattern of [[absorption]] or [[emission]] of [[radiation]] produced by a substance when subjected to energy (radiation, heat, electricity, etc.).
# {{lb|en|mathematics|linear algebra}} The set of [[eigenvalue]]s of a [[matrix]].
#: {{syn|en|eigenspectrum}}
# {{lb|en|mathematics|functional analysis}} 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.
# {{lb|en|[[commutative algebra]]|algebraic geometry}} An [[abstract]] object in mathematics created from a [[commutative ring]] <math>R</math> and denoted <math>\operatorname{Spec}(R)</math> or <math>\operatorname{Spec} R</math> and said to be the ''spectrum of <math>R</math>''; useful in the study of such rings for providing a [[geometric]] object which encodes many of the properties <math>R</math>, and in modern [[geometry]] for [[generalize| generalizing]] the notion of an [[algebraic variety]] to that of an [[affine scheme]]. Formally, the set of all [[prime ideal]]s <math>R</math> 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]] <math>D_f</math> which assigns the localization of <math>R</math> at <math>f</math> to each set <math>D_f</math>, regarded as a ring of functions on <math>D_f</math>. See {{pedia|Spectrum of a ring}}
#: {{hypernyms|en|scheme}}
#: {{hyponyms|en|Stone space}}
# {{lb|en|obsolete}} [[specter|Specter]], [[apparition]]. {{defdate|from early 17th c.}}
# The [[image]] of something [[see]]n that persists after the [[eye]]s are [[close]]d.

====Derived terms====
{{col|en|autism spectrum|cepstrum|light spectrum|spectro-|spectrum disorder|political spectrum|absorption spectrum|autism spectrum disorder|autistic spectrum|autistic spectrum disorder|band spectrum|Bloch spectrum|broad-spectrum|broad-spectrum antibiotic|fetal alcohol spectrum disorder|first-order spectrum|full spectrum superiority|full-spectrum superiority|hydrogen spectrum|line spectrum|mass spectrum|nuclear spectrum|on the spectrum|optical spectrum|spectrum analyser|spectrum analyzer|spread spectrum communication|emission spectrum|schizophrenia spectrum|narrow-spectrum}}

====Related terms====
* {{l|en|spectral}}

====Translations====
{{trans-top|range}}
* Belarusian: {{t|be|спектр|m}}
* Bulgarian: {{t+|bg|спектър|m}}
* Chinese:
*: Mandarin: {{t+|cmn|範圍|tr=fànwéi}}
* Finnish: {{t+|fi|kirjo}}
* French: {{t+|fr|spectre|m}}
* Georgian: {{t|ka|სპექტრი}}
* Greek: {{t+|el|φάσμα|n}}
* Irish: {{t|ga|speictream|m}}
* Italian: {{t+|it|spettro}}
* Japanese: {{t+|ja|スペクトル|tr=supekutoru}}
* Korean: {{t+|ko|스펙트럼}}
* Persian: {{t+|fa|طیف|tr=teyf}}
* Polish: {{t+|pl|spektrum|n}}
* Portuguese: {{t+|pt|espectro|m}} {{q|Brazil|Portugal}}, {{t|pt|espetro|m}} {{q|Portugal}}
* Romanian: {{t+|ro|spectru|n}}
* Russian: {{t+|ru|спектр|m}}, {{t+|ru|диапазо́н|m}}
* Spanish: {{t+|es|espectro|m}}
* Tagalog: {{t+|tl|balangaw}}
* Thai: {{t|th|สเปกตรัม}}
* Ukrainian: {{t|uk|спектр|m}}
{{trans-bottom}}

{{trans-top|range of colors}}
* Afrikaans: {{t|af|spektrum}}
* Albanian: {{t|sq|spektri}}
* Arabic: {{t|ar|طَيْف|m}}
* Armenian: {{t+|hy|սպեկտր}}
* Basque: {{t|eu|espektro}}
* Bulgarian: {{t+|bg|спектър|m}}
* Catalan: {{t+|ca|espectre|m}}
* Chinese:
*: Cantonese: {{t|yue|光譜|tr=gwong1 pou2}}
*: Hakka: {{t|hak|光譜|tr=kông-phú}}
*: Mandarin: {{t+|cmn|光譜|tr=guāngpǔ}}
* Czech: {{t|cs|spektrum|n}}
* Danish: {{t|da|spektrum|n}}, {{t|da|spekter|n}}
* Dutch: {{t+|nl|spectrum|n}}
* Esperanto: {{t|eo|spektro}}
* Estonian: {{t|et|spekter}}
* Finnish: {{t+|fi|kirjo}}, {{t+|fi|spektri}}
* French: {{t+|fr|spectre|m}}
* Galician: {{t+|gl|espectro|m}}
* Georgian: {{t|ka|სპექტრი}}
* German: {{t+|de|Spektrum|n}}
* Greek: {{t+|el|φάσμα|n}}, {{t|el|φωτόφασμα|n}}
* Hebrew: {{t+|he|ספקטרום|tr=spéktrum}}
* Hungarian: {{t+|hu|spektrum}}, {{t+|hu|színkép}}
* Irish: {{t|ga|speictream|m}}
* Italian: {{t+|it|spettro}}
* Japanese: {{t+|ja|スペクトル|tr=supekutoru}}, {{t+|ja|分光|tr=ぶんこう, bunkō}}
* Korean: {{t+|ko|분광(分光)}}
* Kurdish:
*: Northern Kurdish: {{t+|kmr|şebeng|f}}
* Latvian: {{t|lv|spektrs|m}}
* Lithuanian: {{t|lt|spektras|m}}
* Macedonian: {{t|mk|спектар|m}}
* Maori: {{t|mi|tūāwhiorangi}}
* Norwegian:
*: Bokmål: {{t|nb|spektrum|n}}, {{t|nb|spekter|n}}
*: Nynorsk: {{t|nn|spektrum|n}}, {{t|nn|spekter|n}}
* Persian: {{t+|fa|طیف|tr=teyf}}, {{t+|fa|بیناب|tr=binâb}}
* Polish: {{t+|pl|widmo|n}}
* Portuguese: {{t+|pt|espectro|m}} {{q|Brazil|Portugal}}, {{t|pt|espetro|m}} {{q|Portugal}}
* Romanian: {{t+|ro|spectru|n}}
* Russian: {{t+|ru|спектр|m}}
* Serbo-Croatian:
*: Cyrillic: {{t|sh|спектар|m}}
*: Roman: {{t+|sh|spektar|m}}
* Slovak: {{t|sk|spektrum|n}}
* Slovene: {{t+|sl|spekter|m}}
* Spanish: {{t+|es|espectro|m}}
* Swedish: {{t+|sv|spektrum|n}}
* Tagalog: {{t+|tl|balangaw}}
* Telugu: {{t+|te|వర్ణమాల}}
* Thai: {{t|th|สเปกตรัม}}
* Turkish: {{t+|tr|tayf}}
* Ukrainian: {{t|uk|спектр|m}}
* Vietnamese: {{t+|vi|quang phổ}} ({{t|vi|光譜}})
* Volapük: {{t+|vo|späktrum}}, {{t|vo|kölaspäktrum}}
{{trans-bottom}}

{{trans-top|psychology: the autism spectrum}}
* Chinese:
*: Mandarin: {{t+|cmn|譜系}}
* Spanish: {{t+|es|espectro|m}}
{{trans-bottom}}

{{trans-top|chemistry: a pattern of absorption or emission of radiation}}
* Finnish: {{t+|fi|spektri}}
* French: {{t+|fr|spectre|m}}
* German: {{t+|de|Spektrum|n}}
* Greek: {{t+|el|φάσμα|n}}
* Irish: {{t|ga|speictream|m}}
* Japanese: {{t+|ja|スペクトル|tr=supekutoru}}
* Khmer: {{t|km|ស្ប៊ិច}}
* Maori: {{t|mi|tūāwhiorangi}}
* Persian: {{t+|fa|بیناب|tr=binâb}}
* Portuguese: {{t+|pt|espectro|m}} {{q|Brazil|Portugal}}, {{t|pt|espetro|m}} {{q|Portugal}}
{{trans-bottom}}

{{trans-top|linear algebra: set of scalar values}}
* Finnish: {{t+|fi|spektri}}
* French: {{t+|fr|spectre|m}}
* German: {{t+|de|Spektrum|n}}
* Greek: {{t+|el|φάσμα|n}}
* Irish: {{t|ga|speictream|m}}
* Italian: {{t+|it|spettro}}
* Japanese: {{t+|ja|スペクトル|tr=supekutoru}}
* Portuguese: {{t+|pt|espectro|m}} {{q|Brazil|Portugal}}, {{t|pt|espetro|m}} {{q|Portugal}}
* Romanian: {{t+|ro|spectru|n}}
* Russian: {{t+|ru|спектр|m}}
{{trans-bottom}}

{{checktrans-top}}
* German: {{t+check|de|Spektrum|n}} (1, 2, 3)
* Swedish: {{t+check|sv|spektrum|n}} (2, 3)
{{trans-bottom}}

===Anagrams===
* {{anagrams|en|a=cemprstu|cepstrum|crumpets}}

{{cln|en|nouns with irregular plurals}}
{{C|en|Energy|Light|Photochemistry}}

==Dutch==
{{wikipedia|lang=nl}}

===Etymology===
{{root|nl|ine-pro|*speḱ-}}
From {{bor|nl|la|spectrum|t=appearance, image, apparition}}, from {{m|la|speciō|t=look at, view}}.

===Pronunciation===
* {{audio|nl|Nl-spectrum.ogg}}

===Noun===
{{nl-noun|n|-s|pl2=spectra|+}}

# {{l|en|spectrum}}

====Derived terms====
* {{l|nl|spectraal}}
* {{l|nl|spectroscoop}}

==Latin==

===Etymology===
{{root|la|ine-pro|*speḱ-}}

From {{suffix|la|specio|trum|alt1=spec(iō)|gloss1=look at, behold}} (making it a [[doublet]] of {{m|la|speculum}}).

The only attestation in Classical antiquity is in a pair of letters between Cicero and Cassius Longinus which imply that the [[w:Epicureanism|Epicurean]] [[w:Catius|Catius]] (fl. c. 50s–40s BC) used ''spectrum'' as a translation of the Greek philosophical term {{m|grc|εἴδωλον|t=image}}.<ref>"Why is Latin ''spectrum'' a Bad Translation of Epicurus’ ΕΙΔΩΛΟΝ?", Sean McConnell, 2018. ''Mnemosyne'' 72 (2019) 154-162.</ref> It may therefore have been coined by Catius as a neologism, although alternatively, it could be an undocumented but preexisting word that he repurposed as a technical term.

After Cicero, the word is extremely sparsely attested until being revived around the start of the sixteenth century by Renaissance humanist authors with the meaning "apparition" or "phantom", possibly influenced by the fact that Greek εἴδωλον also had this sense.<ref>"Spectrum : Probleme einer Wortgeschichte, vom Altertum zur Neuzeit", Mario Puelma, 1985. ''Museum Helveticum''
Vol. 42, No. 2. page 230</ref>

The scientific use to refer to the [[w:Visible Spectrum|visible spectrum]] of colored light was first introduced by Isaac Newton, who used the word in the second half of the seventeenth century in both his English writings and in his first Latin draft of the ''Opticks,'' the ''Fundamentum Opticae,'' although the 1706 Latin translation of ''Opticks'' by Samuel Clarke translates Newton's English ''spectrum'' into Latin as ''imago''.<ref>[https://books.google.com/books?id=0U9aDwAAQBAJ&pg=PA4 ''Newton’s Sensorium: Anatomy of a Concept''], Jamie C. Kassler, 2018, page 4</ref>

===Pronunciation===
* {{la-IPA|spectrum}}

===Noun===
{{la-noun|spectrum<2>}}

# [[appearance]], [[image]]
#* {{Q|la|Cicero|Epistulae ad Familiares|15|16|1|thru=2|quote=fit enim nescio qui ut quasi coram adesse videare cum scribo aliquid ad te, neque id κατ’ εἰδ<ώλ>ων φαντασίας, ut dicunt tui amici novi, qui putant etiam διανοητικὰς φαντασίας '''spectris''' Catianis excitari. nam, ne te fugiat, Catius Insuber Ἐπικούρειος, qui nuper est mortuus, quae ille Gargettius et iam ante Democritus εἴδωλα, hic '''spectra''' nominat. his autem '''spectris''' etiam si oculi possent feriri, quod <pup>ulis ipsa incurrunt, animus qui possit ego non video; doceas tu me oportebit cum salvus veneris. in meane potestate ut sit '''spectrum''' tuum, ut, simul ac mihi collibitum sit de te cogitare, illud occurrat? neque solum de te, qui mihi haeres in medullis, sed si insulam Britanniam coepero cogitare, eius εἴδωλον mihi advolabit ad pectus?|trans=For somehow it makes you seem almost present when I write anything to you, and that not 'by way of phantoms of images,' as your new friends express it, who hold that 'mental pictures' are caused by what Catius called ''''spectres'''' — for I must remind you that Catius Insuber the Epicurean, lately dead, calls ''''spectres'''' what the famous Gargettius, and before him Democritus, used to call 'images.' Well, even if my eyes were capable of being struck by these ''''spectres''',' because they spontaneously run in upon them at your will, I do not see how the mind can be struck. You will be obliged to explain it to me, when you return safe and sound, whether the ''''spectre'''' of you is at my command, so as to occur to me as soon as I have taken the fancy to think about you; and not only about you, who are in my heart's core, but supposing I begin thinking about the island of Britain — will its image fly at once into my mind?|transyear=1900|transauthor=Evelyn Shuckburgh<ref>Evelyn Shuckburgh, ''[https://books.google.com/books?id=l49fAAAAMAAJ&pg=PA174 Cicero: The Whole Extant Correspondence in Chronological Order]'' (London 1900)</ref>}}
# [[apparition]], [[specter]], [[phantom]]
#* {{Q|la|Desiderius Erasmus|Exorcismus sive spectrum|year=1524|quote=Iam pridem vagabatur rumor ac fabula per eius loci rusticos, iuxta ponticulum hunc observari '''spectrum''' quoddam, cuius subinde exaudirentur miserandi eiulatus: suspicabantur, animam esse cuiuspiam, quae diris cruciatibus torqueretur.}}
# {{lb|la|New Latin}} {{l|en|spectrum}} {{gl|band of light arranged in order by wavelength}}
#* {{Q|la|Isaac Newton|Fundamentum Opticae<ref>[https://books.google.com/books?id=YAEbEAAAQBAJ&pg=PA258 ''The Optical Papers of Isaac Newton''], Vol. II. Edited Alan E. Shapiro, 2021. Pages 258-259.</ref>||year=c. 1687-88|quote=Considerabam praeterea quod latitudine foraminis ''F'' per quod lux in cubiculum ingreditur fit penumbra in circuitu '''spectri''' ''Y'', et penumbra illa permanet in lateribus rectilineis '''spectrorum''' ''PT'' et ''pt.''|trans=I further considered that by the breadth of the hole ''F'', through which the light enters the room, a penumbra is made in the border of the '''spectrum''' ''Y'', and that penumbra remains in the straight sides of the '''spectra''' ''PT'' and ''pt''.|transauthor=Alan E. Shapiro}}

====Declension====
{{la-ndecl|spectrum<2>}}

====Synonyms====
* {{l|la|īdōlum}}, {{l|la|simulācrum}}, {{l|la|imāgō}},  {{l|la|speciēs}}, {{l|la|figūra}}, {{l|la|fōrma}}, {{l|la|effigiēs}}, {{l|la|phantasma}}

====Related terms====
* {{l|la|speciō}}
* {{l|la|spectiō}}
* {{l|la|spectō}}

====Descendants====
* {{desc|ca|espectre|bor=1}}
* {{desc|nl|spectrum|bor=1}}
* {{desc|bor=1|en|spectre|specter}}; {{l|en|spectrum}}
* {{desc|fr|spectre|bor=1}}
* {{desc|de|Spektrum|bor=1}}
* {{desc|ga|speictream|bor=1}}
* {{desc|it|spettro|bor=1}}
* {{desc|pl|spektrum|bor=1}}
* {{desc|pt|espectro|bor=1}}
* {{desc|ro|spectru|bor=1}}
* {{desc|ru|спектр|bor=1}}
* {{desc|es|espectro|bor=1}}
* {{desc|sv|spektrum|bor=1}}

===References===
<references/>

===Further reading===
* {{R:L&S}}
* {{R:Elementary Lewis}}
* {{R:du Cange}}
* {{R:Gaffiot}}