redshift
UK[ˈredʃɪft]US[ˈredʃɪft]
n
a shift of spectral lines toward longer wavelengths, observed in the light from distant galaxies and interpreted as a Doppler effect due to the expansion of the universe.
n
(also redshifted) the property of having undergone such a shift.
Morpheme Breakdown
red
shift
red
color
shift
change
Etymology
the term is a modern english compound, formed in the early 20th century within the field of astrophysics. it combines the color 'red', representing the longer wavelength end of the visible spectrum, with 'shift', indicating a change in position. the logic is literal and descriptive: when light from a receding celestial object is stretched due to the doppler effect, its spectral lines move toward the red end of the spectrum. thus, 'redshift' directly names the observed phenomenon, where the color metaphorically signifies the direction of the wavelength change caused by cosmic expansion.
Analysis
Structure: red (color) + shift (change)
red (from old english 'read', meaning the color red); shift (from old english 'sciftan', meaning to arrange, divide, or change position).
Examples
the observed redshift of the galaxy indicated it was moving away from us at a tremendous speed.
astronomers use the degree of redshift to estimate the distance of celestial objects.
a greater redshift corresponds to a faster recessional velocity due to the expansion of the universe.