The Collaborative International Dictionary of English v.0.48:

Assize \As*size"\, n. [OE. assise, asise, OF. assise, F.
   assises, assembly of judges, the decree pronounced by them,
   tax, impost, fr. assis, assise, p. p. of asseoir, fr. L.
   assid?re to sit by; ad + sed[=e]re to sit. See Sit, Size,
   and cf. Excise, Assess.]
   1. An assembly of knights and other substantial men, with a
      bailiff or justice, in a certain place and at a certain
      time, for public business. [Obs.]
      [1913 Webster]

   2. (Law)
      (a) A special kind of jury or inquest.
      (b) A kind of writ or real action.
      (c) A verdict or finding of a jury upon such writ.
      (d) A statute or ordinance in general. Specifically: (1) A
          statute regulating the weight, measure, and
          proportions of ingredients and the price of articles
          sold in the market; as, the assize of bread and other
          provisions; (2) A statute fixing the standard of
          weights and measures.
      (e) Anything fixed or reduced to a certainty in point of
          time, number, quantity, quality, weight, measure,
          etc.; as, rent of assize. --Glanvill. --Spelman.
          --Cowell. --Blackstone. --Tomlins. --Burrill.

   Note: [This term is not now used in England in the sense of a
         writ or real action, and seldom of a jury of any kind,
         but in Scotch practice it is still technically applied
         to the jury in criminal cases. --Stephen. --Burrill.
         --Erskine.]
      (f) A court, the sitting or session of a court, for the
          trial of processes, whether civil or criminal, by a
          judge and jury. --Blackstone. --Wharton. --Encyc.
          Brit.
      (g) The periodical sessions of the judges of the superior
          courts in every county of England for the purpose of
          administering justice in the trial and determination
          of civil and criminal cases; -- usually in the plural.
          --Brande. --Wharton. --Craig. --Burrill.
      (h) The time or place of holding the court of assize; --
          generally in the plural, assizes.
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   3. Measure; dimension; size. [In this sense now corrupted
      into size.]
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            An hundred cubits high by just assize. --Spenser.
      [1913 Webster] [Formerly written, as in French, assise.]
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