| Definition/Meaning | Word/Phrase |
|---|
| (astronomy) the magnitude that a star would have if it were viewed from a distance of 10 parsecs (32.62 light years) from the earth |
absolute magnitude
|
| measure of the rate of decrease in the intensity of electromagnetic radiation (as light) as it passes through a given substance; the fraction of incident radiant energy absorbed per unit mass or thickness of an absorber |
absorptance
,
absorption coefficient
,
coefficient of absorption
|
| dark band in the spectrum of white light that has been transmitted through a substance that exhibits absorption at selective wavelengths |
absorption band
|
| deep sea (2000 meters or more) where there is no light |
abyssal zone
|
| common North American maple tree; five-lobed leaves are light green above and silvery white beneath; source of hard close-grained but brittle light-brown wood |
Acer saccharinum
,
silver maple
|
| (physiology) the responsive adjustment of a sense organ (as the eye) to varying conditions (as of light) |
adaptation
|
| one of 7 to 12 sons of Aditi; gods of celestial light |
Aditya
|
| light, as gases |
aeriform
|
| light midafternoon meal of tea and sandwiches or cakes |
afternoon tea
,
tea
,
teatime
|
| Spanish grass with light feathery panicles grown for dried bouquets |
Agrostis nebulosa
,
cloud grass
|
| chief deity of Zoroastrianism; source of light and embodiment of good |
Ahura Mazda
,
Ormazd
,
Ormuzd
|
| very light white |
alabaster
|
| bishop, light blow on cheek given at confirmation service by |
alapa
|
| light reflected by celestial body |
albedo
|
| ratio of reflected to incident light |
albedo
,
reflective power
|
| physicist born in Germany who formulated the special theory of relativity and the general theory of relativity; Einstein also proposed that light consists of discrete quantized bundles of energy (later called photons) (1879-1955) |
Albert Einstein
,
Einstein
|
| Old World willow with light green leaves cultivated for use in basketry |
almond willow
,
black Hollander
,
Salix amygdalina
,
Salix triandra
|
| North American shrub with light green leaves and winged nuts |
Alnus crispa
,
Alnus veridis crispa
,
green alder
|
| shrub or small tree of southeastern United States having soft light brown wood |
Alnus maritima
,
seaside alder
|
| tall timber tree with hard heavy pinkish or light brown wood |
alpine ash
,
Eucalyptus delegatensis
,
mountain oak
|
