The Collaborative International Dictionary of English v.0.48:

Denomination \De*nom`i*na"tion\, n. [L. denominatio metonymy:
   cf. F. d['e]nomination a naming.]
   1. The act of naming or designating.
      [1913 Webster]

   2. That by which anything is denominated or styled; an
      epithet; a name, designation, or title; especially, a
      general name indicating a class of like individuals; a
      category; as, the denomination of units, or of thousands,
      or of fourths, or of shillings, or of tons.
      [1913 Webster]

            Those [qualities] which are classed under the
            denomination of sublime.              --Burke.
      [1913 Webster]

   3. A class, or society of individuals, called by the same
      name; a sect; as, a denomination of Christians.

   Syn: Name; appellation; title. See Name.
        [1913 Webster]

WordNet (r) 3.0 (2006):

denomination
    n 1: a group of religious congregations having its own
         organization and a distinctive faith
    2: a class of one kind of unit in a system of numbers or
       measures or weights or money; "he flashed a fistful of bills
       of large denominations"
    3: identifying word or words by which someone or something is
       called and classified or distinguished from others [syn:
       appellation, denomination, designation, appellative]

Moby Thesaurus II by Grady Ward, 1.0:

221 Moby Thesaurus words for "denomination":
   Amish, Anglicanism, Anglo-Catholicism, Arianism, Athanasianism,
   Boehmenism, Calvinism, Catholicism, Christian Science,
   Confucianism, Congregationalism, Conservative Judaism,
   Eleusinianism, Episcopalianism, Erastianism, Ethical Culture,
   Gnosticism, Hinduism, Judaism, Lamaism, Laudianism, Laudism,
   Lingayat Hinduism, Magianism, Mahayana Buddhism, Mandaeism,
   Methodism, Mithraism, Muhammadanism, New Thought,
   Orthodox Christianity, Orthodox Judaism, Oxford Movement, Parsiism,
   Parsism, Practical Christianity, Puritanism, Quakerism,
   Reform Judaism, Roman Catholicism, Rosicrucianism, Sabaeanism,
   Salvation Army, Shiite Muslimism, Shin Buddhism, Shingon Buddhism,
   Shinto, Shintoism, Sikhism, Socinianism, Sufism, Taoism,
   Tendai Buddhism, Theosophy, Ubiquitarianism, Uniatism,
   Unitarianism, Vaishnavite Hinduism, Vajrayana Buddhism, Vedanta,
   Wahabiism, Yoga, Yogism, Zen, Zen Buddhism, Zoroastrianism,
   adherents, affiliation, allocation, antinomianism, appellation,
   appellative, assignment, attribution, baptism, binomen,
   binomial name, blood, body, branch, brand, breed, byword, calling,
   cast, character, characterization, christening, church, clan,
   class, classification, classifying, cognomen, color, communion,
   community, confession, connection, creed, cryptonym, cult,
   definition, denotation, description, designation, determination,
   differentiation, disciples, disclosure, division, empty title,
   epithet, eponym, euonym, expression, faction, faith, feather,
   fellowship, fingering, fixing, followers, form, genre, genus,
   grade, grain, group, gymnosophy, handle, hint, homoiousianism,
   honorific, hyponym, identification, identifying, ilk, indication,
   indicativeness, ism, kidney, kin, kind, label, latitudinarianism,
   line, lot, make, manifestation, manner, mark, meaning, mold,
   moniker, name, namesake, naming, nature, nicknaming, nomen,
   nomen nudum, number, offshoot, order, organization, party,
   persuasion, phylum, picking out, pinning down, pointing,
   pointing out, pointing to, precision, proper name, proper noun,
   quietism, race, religious order, schism, school, scientific name,
   secret name, sect, sectarism, segment, selection, shape, show,
   showing, signification, size, society, sort, species,
   specification, stamp, stipulation, strain, stripe, style, styling,
   suggestion, symptomaticness, tag, tagging, tautonym, term, terming,
   the like of, the likes of, title, tribe, trinomen, trinomial name,
   type, unit, value, variety, version