from
The Collaborative International Dictionary of English v.0.48
Cardinal \Car"di*nal\, a. [L. cardinalis, fr. cardo the hinge of
a door, that on which a thing turns or depends: cf. F.
cardinal.]
Of fundamental importance; pre["e]minent; superior; chief;
principal.
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The cardinal intersections of the zodiac. --Sir T.
Browne.
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Impudence is now a cardinal virtue. --Drayton.
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But cardinal sins, and hollow hearts, I fear ye.
--Shak.
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{Cardinal numbers}, the numbers one, two, three, etc., in
distinction from first, second, third, etc., which are
called {ordinal numbers}.
{Cardinal points}
(a) (Geol.) The four principal points of the compass, or
intersections of the horizon with the meridian and the
prime vertical circle, north, south east, and west.
(b) (Astrol.) The rising and setting of the sun, the zenith
and nadir.
{Cardinal signs} (Astron.) Aries, Libra, Cancer, and
Capricorn.
{Cardinal teeth} (Zool.), the central teeth of bivalve shell.
See {Bivalve}.
{Cardinal veins} (Anat.), the veins in vertebrate embryos,
which run each side of the vertebral column and returm the
blood to the heart. They remain through life in some
fishes.
{Cardinal virtues}, pre["e]minent virtues; among the
ancients, prudence, justice, temperance, and fortitude.
{Cardinal winds}, winds which blow from the cardinal points
due north, south, east, or west.
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