Extending far below the surface; of great perpendicular
dimension (measured from the surface downward, and distinguished from
high, which is measured upward); far to the bottom; having a
certain depth; as, a deep sea.
Extending far back from the front or outer
part; of great horizontal dimension (measured backward from the front
or nearer part, mouth, etc.); as, a deep cave or recess or
wound; a gallery ten seats deep; a company of soldiers six
files deep.
Low in situation; lying far below the
general surface; as, a deep valley.
Hard to penetrate or comprehend; profound;
-- opposed to shallow or superficial; intricate;
mysterious; not obvious; obscure; as, a deep subject or
plot.
Of penetrating or far-reaching intellect;
not superficial; thoroughly skilled; sagacious; cunning.
Profound; thorough; complete; unmixed;
intense; heavy; heartfelt; as, deep distress; deep
melancholy; deep horror.
Strongly colored; dark; intense; not light
or thin; as, deep blue or crimson.
Of low tone; full-toned; not high or
sharp; grave; heavy.
Muddy; boggy; sandy; -- said of
roads.
In celebration of Noah Webster's Birthday (October 16, 2009), we have prepared an updated website. 
pr, Sw. diup, Dan.
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