The Collaborative International Dictionary of English v.0.48:

Designation \Des`ig*na"tion\, n. [L. designatio: cf. F.
   d['e]signation.]
   1. The act of designating; a pointing out or showing;
      indication.
      [1913 Webster]

   2. Selection and appointment for a purpose; allotment;
      direction.
      [1913 Webster]

   3. That which designates; a distinguishing mark or name;
      distinctive title; appellation.
      [1913 Webster]

            The usual designation of the days of the week.
                                                  --Whewell.
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   4. Use or application; import; intention; signification, as
      of a word or phrase.
      [1913 Webster]

            Finite and infinite seem . . . to be attributed
            primarily, in their first designation, only to those
            things which have parts.              --Locke.
      [1913 Webster]

WordNet (r) 3.0 (2006):

designation
    n 1: identifying word or words by which someone or something is
         called and classified or distinguished from others [syn:
         appellation, denomination, designation,
         appellative]
    2: the act of putting a person into a non-elective position;
       "the appointment had to be approved by the whole committee"
       [syn: appointment, assignment, designation, naming]
    3: the act of designating or identifying something [syn:
       designation, identification]

Moby Thesaurus II by Grady Ward, 1.0:

121 Moby Thesaurus words for "designation":
   allocation, appellation, appellative, appointment, assignment,
   attribution, baptism, binomen, binomial name, blood, brand, breed,
   byword, calling, cast, character, characterization, christening,
   clan, classification, cognomen, color, cryptonym, definition,
   denomination, denotation, description, determination,
   differentiation, disclosure, empty title, epithet, eponym, euonym,
   expression, feather, fingering, fixing, form, genre, genus, grain,
   handle, hint, honorific, hyponym, identification, ilk, indication,
   indicativeness, kidney, kin, kind, label, line, lot, make,
   manifestation, manner, mark, meaning, mold, moniker, name,
   namesake, naming, nature, nicknaming, nomen, nomen nudum,
   nomination, number, ordainment, ordination, persuasion, phylum,
   picking out, pigeonhole, pigeonholing, pinning down, pointing,
   pointing out, pointing to, posting, precision, proper name,
   proper noun, proposal, race, recognition, scientific name,
   secret name, selection, shape, show, showing, signification, sort,
   species, specification, stamp, stipulation, strain, stripe, style,
   styling, suggestion, symptomaticness, tabbing, tag, tautonym,
   terming, the like of, the likes of, title, transferral, tribe,
   trinomen, trinomial name, type, variety



Bouvier's Law Dictionary, Revised 6th Ed (1856):

DESIGNATION, wills. The expression used by a testator, instead of the name
of the person or the thing he is desirous to name; for example, a legacy to.
the eldest son of such a person, would be a designation of the legatee. Vide
1 Rop. Leg. ch. 2.
     2. A bequest of the farm which the testator bought of such a person; or
of the picture he owns, painted by such an artist, would be a designation of
the thing devised or bequeathed.