The Collaborative International Dictionary of English v.0.48:

Firm \Firm\, a. [Compar. Firmer; superl. Firmest.] [OE.
   ferme, F. ferme, fr.L. firmus; cf. Skr. dharman support, law,
   order, dh? to hold fast, carry. Cf. Farm, Throne.]
   1. Fixed; hence, closely compressed; compact; substantial;
      hard; solid; -- applied to the matter of bodies; as, firm
      flesh; firm muscles, firm wood.
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   2. Not easily excited or disturbed; unchanging in purpose;
      fixed; steady; constant; stable; unshaken; not easily
      changed in feelings or will; strong; as, a firm believer;
      a firm friend; a firm adherent.
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            Under spread ensigns, moving nigh, in slow
            But firm battalion.                   --Milton.
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            By one man's firm obediency fully tried. --Milton.
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   3. Solid; -- opposed to fluid; as, firm land.
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   4. Indicating firmness; as, a firm tread; a firm countenance.

   Syn: Compact; dense; hard; solid; stanch; robust; strong;
        sturdly; fixed; steady; resolute; constant.
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