nosedive

from WordNet (r) 3.0 (2006)

nosedive
    n 1: a sudden sharp drop or rapid decline; "the stock took a
         nosedive"
    2: a steep nose-down descent by an aircraft [syn: {dive}, {nose
       dive}, {nosedive}]
    v 1: plunge nose first; drop with the nose or front first, of
         aircraft

from The Collaborative International Dictionary of English v.0.48

nosedive \nose"dive`\, nose-dive \nose"-dive`\v. i.
   To drop with the nose or front first, as of an airplane.

   Syn: nosedive.
        [WordNet 1.5]

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