The Collaborative International Dictionary of English v.0.48:

Memorial \Me*mo"ri*al\, a. [F. m['e]morial, L. memorialis, fr.
   memoria. See Memory.]
   [1913 Webster]
   1. Serving to preserve remembrance; commemorative; as, a
      memorial building.
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            There high in air, memorial of my name,
            Fix the smooth oar, and bid me live to fame. --Pope.
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   2. Contained in memory; as, a memorial possession.
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   3. Mnemonic; assisting the memory.
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            This succession of Aspirate, Soft, and Hard, may be
            expressed by the memorial word ASH.   --Skeat.
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   Memorial Day. See Memorial Day in the vocabulary. Also
      called Decoration Day. [U.S.]
      [1913 Webster +PJC]

The Collaborative International Dictionary of English v.0.48:

Memorial \Me*mo"ri*al\, n. [Cf. F. m['e]morial.]
   1. Anything intended to preserve the memory of a person or
      event; something which serves to keep something else in
      remembrance; a monument. --Macaulay.
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            Churches have names; some as memorials of peace,
            some of wisdom, some in memory of the Trinity
            itself.                               --Hooker.
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   2. A memorandum; a record. [Obs. or R.] --Hayward.
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   3. A written representation of facts, addressed to the
      government, or to some branch of it, or to a society,
      etc., -- often accompanied with a petition.
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   4. Memory; remembrance. [Obs.]
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            Precious is the memorial of the just. --Evelyn.
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   5. (Diplomacy) A species of informal state paper, much used
      in negotiation.
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WordNet (r) 3.0 (2006):

memorial
    n 1: a recognition of meritorious service [syn: memorial,
         commemoration, remembrance]
    2: a written statement of facts submitted in conjunction with a
       petition to an authority
    3: a structure erected to commemorate persons or events [syn:
       memorial, monument]