Spectrum
/ˈspɛk.trəm/noun
A range of colors, wavelengths, or related values; more broadly, a continuous range of related things.
Did you know?The word entered scientific English through Isaac Newton’s optics, but its deepest root is tied to Latin *specere*, “to look,” the same root behind words for seeing, spying, and spectacles.
Etymological Timeline
Proto-Indo-European
PIE
*spek-
“to look, observe”
Latin
Latin
specere
“to look at, behold”
Latin
Latin
spectrum
“an appearance, image, apparition”
17th Century
English
spectrum
“a ghostly apparition or specter; later, an optical image formed by a prism”
Modern English
English
spectrum
“a range of colors or other continuous gradations”