The Collaborative International Dictionary of English v.0.48:

Stiff \Stiff\, a. [Compar. Stiffer; superl. Stiffest.] [OE.
   stif, AS. st[imac]f; akin to D. stijf, G. steif, Dan. stiv,
   Sw. styf, Icel. st[imac]fr, Lith. stipti to be stiff; cf. L.
   stipes a post, trunk of a tree, stipare to press, compress.
   Cf. Costive, Stifle, Stipulate, Stive to stuff.]
   1. Not easily bent; not flexible or pliant; not limber or
      flaccid; rigid; firm; as, stiff wood, paper, joints.
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            [They] rising on stiff pennons, tower
            The mid aerial sky.                   --Milton.
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   2. Not liquid or fluid; thick and tenacious; inspissated;
      neither soft nor hard; as, the paste is stiff.
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   3. Firm; strong; violent; difficult to oppose; as, a stiff
      gale or breeze.
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   4. Not easily subdued; unyielding; stubborn; obstinate;
      pertinacious; as, a stiff adversary.
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            It is a shame to stand stiff in a foolish argument.
                                                  --Jer. Taylor.
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            A war ensues: the Cretans own their cause,
            Stiff to defend their hospitable laws. --Dryden.
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   5. Not natural and easy; formal; constrained; affected;
      starched; as, stiff behavior; a stiff style.
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            The French are open, familiar, and talkative; the
            Italians stiff, ceremonious, and reserved.
                                                  --Addison.
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   6. Harsh; disagreeable; severe; hard to bear. [Obs. or
      Colloq.] "This is stiff news." --Shak.
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   7. (Naut.) Bearing a press of canvas without careening much;
      as, a stiff vessel; -- opposed to crank. --Totten.
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   8. Very large, strong, or costly; powerful; as, a stiff
      charge; a stiff price. [Slang]
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   Stiff neck, a condition of the neck such that the head can
      not be moved without difficulty and pain.
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   Syn: Rigid; inflexible; strong; hardly; stubborn; obstinate;
        pertinacious; harsh; formal; constrained; affected;
        starched; rigorous.
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