spectrum English · revision 6690

+ {{infobox|confidence=established|formation=borrowing|attested=1611|origins=la specio}}

+

+ ==Pronunciation==

+ * IPA: /ˈspɛktɹəm/^(Wiktionary)

+

+ ==Etymology==

+ It is [[bor|la|spectrum|t=appearance, image, apparition]],^(Barnhart 1988)^(Etymonline)^(MWU 2024) from [[m|la|specio|alt=specere|t=to look at]] (see [[spectre]] and [[spy]]),^(Barnhart 1988)^(Etymonline)^(NODE 1998) from PIE [[ine-pro|*speḱ-|alt=*spek-|t=to observe]].^(Etymonline)

+

+ ==Earliest recorded meaning==

+ An apparition or spectre: 1611, in John Speed's ''History of Great Britain'';^(Barnhart 1988)^(OED 1989) this sense is now obsolete or archaic.^(Etymonline)^(SOED 2002)

+

+ ==Semantic evolution==

+ The coloured band formed when a beam of light passes through a prism is first recorded in 1671, in Newton's writings.^(Barnhart 1988)^(OED 1989) An after-image left on the retina is from 1786.^(OED 1989) The whole range of wavelengths of electromagnetic radiation is by 1888,^(Etymonline)^(OED 1989) and an arrangement of the parts of any phenomenon by degree from 1887.^(OED 1989) The figurative sense, the entire range of something, as in ''the political spectrum'', is from 1936.^(Etymonline)^(OED 1989)

+

+ ==Timeline==

+ * 1611 – an apparition.^(Barnhart 1988)^(OED 1989)

+ * 1671 – the colours of light, in Newton.^(Barnhart 1988)^(OED 1989)

+ * 1786 – an after-image.^(OED 1989)

+ * 1888 – the range of wavelengths.^(Etymonline)^(OED 1989)

+ * 1936 – any full range.^(Etymonline)^(OED 1989)

+

+ ==Modern meaning==

+ ===Noun===

+ # The band of colours, from [[red]] to [[violet]], formed when white light is split by a [[prism]].^(AHD)^(Collins 2023)

+ # The entire range of [[wavelength|alt=wavelengths]] of [[electromagnetic radiation]], or a part of it: ''the radio spectrum''.^(AHD)^(Collins 2023)

+ # A wide range of related qualities, ideas or activities: ''across the political spectrum''.^(AHD)^(Collins 2023)

+

+ ==Word family==

+ * [[spectro-]]

+ * [[broad-spectrum]]

+ * [[absorption spectrum]]

+ * [[band spectrum]]

+ * [[line spectrum]]

+ * [[mass spectrum]]

+ * [[emission spectrum]]

+

+ ==Related words==

+ * [[spectral]]

+ * [[spectre]]

+ * [[spectacle]]

+ * [[spectator]]

+ * [[spectroscope]]

+ * [[spy]]

+ * [[inspect]]

+

+ ==References==

+ {{reflist}}