from
The Collaborative International Dictionary of English v.0.48
Plunge \Plunge\, v. i.
1. To thrust or cast one's self into water or other fluid; to
submerge one's self; to dive, or to rush in; as, he
plunged into the river. Also used figuratively; as, to
plunge into debt.
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Forced to plunge naked in the raging sea. --Dryden.
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To plunge into guilt of a murther. --Tillotson.
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2. To pitch or throw one's self headlong or violently
forward, as a horse does.
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Some wild colt, which . . . flings and plunges.
--Bp. Hall.
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3. To bet heavily and with seeming recklessness on a race, or
other contest; in an extended sense, to risk large sums in
hazardous speculations. [Cant]
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{Plunging fire} (Gun.), firing directed upon an enemy from an
elevated position.
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