The Collaborative International Dictionary of English v.0.48:

Identification \I*den`ti*fi*ca"tion\, n. [Cf. F.
   identification.]
   The act of identifying, or proving to be the same; also, the
   state of being identified.
   [1913 Webster]

WordNet (r) 3.0 (2006):

identification
    n 1: the act of designating or identifying something [syn:
         designation, identification]
    2: evidence of identity; something that identifies a person or
       thing
    3: the condition of having the identity (of a person or object)
       established; "the thief's identification was followed quickly
       by his arrest"; "identification of the gun was an important
       clue"
    4: the process of recognizing something or someone by
       remembering; "a politician whose recall of names was as
       remarkable as his recognition of faces"; "experimental
       psychologists measure the elapsed time from the onset of the
       stimulus to its recognition by the observer" [syn:
       recognition, identification]
    5: the attribution to yourself (consciously or unconsciously) of
       the characteristics of another person (or group of persons)

Moby Thesaurus II by Grady Ward, 1.0:

156 Moby Thesaurus words for "identification":
   ID card, affiliation, allergy, anaphylaxis, appellation,
   apperception, appraisal, assessment, assimilation, association,
   association by contiguity, association of ideas, authentication,
   badge, baptism, calligram, calling, calling card, card, caring,
   cataloguing, categorization, categorizing, certification,
   characterization, chord, christening, clang association,
   classification, classifying, coalescence, combination, concern,
   connection, considerateness, controlled association, corroboration,
   countermark, countersign, credentials, definition, delicacy,
   denomination, denotation, designation, detection, differentiation,
   disclosure, distinguishing, distinguishment, dog tag, echo,
   empathy, establishment, evaluation, expression, exquisiteness,
   factoring, fellow feeling, fineness, fingering, free association,
   fusion, gauging, grouping, hint, hyperesthesia, hyperpathia,
   hypersensitivity, identification badge, identification tag,
   indication, indicativeness, initials, involvement, irritability,
   letter of introduction, manifestation, meaning, mental linking,
   merger, monogram, naming, negative transference, nervousness,
   nicknaming, oversensibility, oversensitiveness, overtenderness,
   passibility, pathos, perception, perceptiveness, perceptivity,
   photophobia, picking out, pinpointing, pointing, pointing out,
   pointing to, positive transference, press card, prickliness,
   rapport, realization, recognition, reidentification, relating,
   relationship, response, responsiveness, selection, sensitiveness,
   sensitivity, sensitization, serial number, sharing, show, showing,
   sifting, sifting out, signature, signification, soreness, sorting,
   sorting out, specification, stream of consciousness, styling,
   substantiation, suggestion, supersensitivity, sympathetic chord,
   sympathetic response, sympathy, symptomaticness, synesthesia,
   synthesis, tact, tactfulness, tenderness, terming, tessera,
   tetchiness, thin skin, ticklishness, touchiness, transference,
   unification, union, verification, vibes, vibrations, visiting card,
   weighing, winnowing