The Collaborative International Dictionary of English v.0.48:

Halfpace \Half"pace`\ (-p[=a]s`), n. (Arch.)
   A platform of a staircase where the stair turns back in
   exactly the reverse direction of the lower flight. See
   Quarterpace.
   [1913 Webster]

   Note: This term and quarterpace are rare or unknown in the
         United States, platform or landing being used
         instead.
         [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Platform \Plat"form`\, n. [Plat, a. + -form: cf. F. plateforme.]
   1. A plat; a plan; a sketch; a model; a pattern. Used also
      figuratively. [Obs.] --Bacon.
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   2. A place laid out after a model. [Obs.]
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            lf the platform just reflects the order. --Pope.
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   3. Any flat or horizontal surface; especially, one that is
      raised above some particular level, as a framework of
      timber or boards horizontally joined so as to form a roof,
      or a raised floor, or portion of a floor; a landing; a
      dais; a stage, for speakers, performers, or workmen; a
      standing place.
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   4. A declaration of the principles upon which a person, a
      sect, or a party proposes to stand; a declared policy or
      system; as, the Saybrook platform; a political platform.
      "The platform of Geneva." --Hooker.
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   5. (Naut.) A light deck, usually placed in a section of the
      hold or over the floor of the magazine. See Orlop.
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   Platform car, a railway car without permanent raised sides
      or covering; a f?at.

   Platform scale, a weighing machine, with a flat platform on
      which objects are weighed.
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The Collaborative International Dictionary of English v.0.48:

Platform \Plat"form`\, v. t.
   1. To place on a platform. [R.]
      [1913 Webster]

   2. To form a plan of; to model; to lay out. [Obs.]
      [1913 Webster]

            Church discipline is platformed in the Bible.
                                                  --Milton.
      [1913 Webster]

WordNet (r) 3.0 (2006):

platform
    n 1: a raised horizontal surface; "the speaker mounted the
         platform"
    2: a document stating the aims and principles of a political
       party; "their candidate simply ignored the party platform";
       "they won the election even though they offered no positive
       program" [syn: platform, political platform, political
       program, program]
    3: the combination of a particular computer and a particular
       operating system
    4: any military structure or vehicle bearing weapons [syn:
       platform, weapons platform]
    5: a woman's shoe with a very high thick sole [syn: chopine,
       platform]

The Free On-line Dictionary of Computing (19 January 2023):

platform

   Specific computer hardware, as in the phrase
   "platform-independent".  It may also refer to a specific
   combination of hardware and operating system and/or
   compiler, as in "this program has been ported to several
   platforms".  It is also used to refer to support software for
   a particular activity, as in "This program provides a platform
   for research into routing protocols".

   (1994-12-07)