The Collaborative International Dictionary of English v.0.48:

Manner \Man"ner\, n. [OE. manere, F. mani[`e]re, from OF.
   manier, adj., manual, skillful, handy, fr. (assumed) LL.
   manarius, for L. manuarius belonging to the hand, fr. manus
   the hand. See Manual.]
   1. Mode of action; way of performing or effecting anything;
      method; style; form; fashion.
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            The nations which thou hast removed, and placed in
            the cities of Samaria, know not the manner of the
            God of the land.                      --2 Kings
                                                  xvii. 26.
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            The temptations of prosperity insinuate themselves
            after a gentle, but very powerful, manner.
                                                  --Atterbury.
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   2. Characteristic mode of acting, conducting, carrying one's
      self, or the like; bearing; habitual style.
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      (a) Customary method of acting; habit.
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                Paul, as his manner was, went in unto them.
                                                  --Acts xvii.
                                                  2.
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                Air and manner are more expressive than words.
                                                  --Richardson.
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      (b) pl. Carriage; behavior; deportment; also, becoming
          behavior; well-bred carriage and address; as, mind
          your manners!.
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                Good manners are made up of petty sacrifices.
                                                  --Emerson.
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      (c) The style of writing or thought of an author;
          characteristic peculiarity of an artist.
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   3. Certain degree or measure; as, it is in a manner done
      already.
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            The bread is in a manner common.      --1 Sam.
                                                  xxi.5.
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   4. Sort; kind; style; -- in this application sometimes having
      the sense of a plural, sorts or kinds; as, all manners of
      people came to the rally.
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            And they being afraid wondered, saying to one
            another, What manner of man is this! for he
            commandeth even the winds and the water, and they
            obey him.                             --Luke 8: 25.

            Ye tithe mint, and rue, and all manner of herbs.
                                                  --Luke xi. 42.
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            I bid thee say,
            What manner of man art thou?          --Coleridge.
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   Note: In old usage, of was often omitted after manner, when
         employed in this sense. "A manner Latin corrupt was her
         speech." --Chaucer.
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   By any manner of means, in any way possible; by any sort of
      means.

   To be taken in the manner or To be taken with the manner.
      [A corruption of to be taken in the mainor. See Mainor.]
      To be taken in the very act. [Obs.] See Mainor.

   To make one's manners, to make a bow or courtesy; to offer
      salutation.

   Manners bit, a portion left in a dish for the sake of good
      manners. --Hallwell.
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   Syn: Method; mode; custom; habit; fashion; air; look; mien;
        aspect; appearance. See Method.
        [1913 Webster] Mannerchor

WordNet (r) 3.0 (2006):

manner
    n 1: how something is done or how it happens; "her dignified
         manner"; "his rapid manner of talking"; "their nomadic mode
         of existence"; "in the characteristic New York style"; "a
         lonely way of life"; "in an abrasive fashion" [syn:
         manner, mode, style, way, fashion]
    2: a way of acting or behaving [syn: manner, personal
       manner]
    3: a kind; "what manner of man are you?"

Moby Thesaurus II by Grady Ward, 1.0:

246 Moby Thesaurus words for "manner":
   MO, action, actions, activity, acts, address, affectation,
   affectedness, air, algorithm, amenities, angle, appearance,
   approach, area, aspect, attack, attitude, bag, bearing, behavior,
   behavior pattern, behavioral norm, behavioral science, blood,
   bon ton, brand, breed, carriage, cast, ceremony, character,
   civility, clan, color, command of language, complexion,
   comportment, conduct, configuration, conformity, consuetude,
   convention, course, culture pattern, cup of tea, custom, decorum,
   demeanor, denomination, deportment, description, designation,
   doing, doings, effect, eidolon, established way, etiquette,
   exaggeration, expression of ideas, exteriority, externality,
   externalness, extrinsicality, facet, fashion, feather, feature,
   feeling for words, field, figure, folkway, foreignness, form,
   form of speech, formalities, forte, genre, genus, gestalt,
   gestures, goings-on, good form, grace of expression, grain,
   grandiloquence, guise, habit, habitude, idiosyncrasy, ilk, image,
   imago, impression, inflation, kidney, kin, kind, label, light,
   likeness, line, line of action, lineaments, lines, literary style,
   long suit, look, lot, main interest, maintien, make,
   manner of speaking, manner of working, mannerism, manners, mark,
   means, method, methodology, methods, metier, mien, mode,
   mode of expression, mode of operation, mode of procedure, modus,
   modus operandi, modus vivendi, mold, mores, motions, movements,
   moves, nature, niceties, number, observable behavior, observance,
   openness, order, outerness, outward appearance, outwardness,
   pattern, peculiarity, personal style, persuasion, pet subject,
   phase, phasis, phylum, poise, politeness, politesse, port, pose,
   posture, practice, praxis, prescription, presence, procedure,
   proceeding, process, proper thing, proprieties, protocol, pursuit,
   race, reference, regard, respect, rhetoric, ritual, routine,
   seeming, semblance, sense of language, shallowness, shape, side,
   simulacrum, slant, social code, social convention, social graces,
   social science, sort, specialism, speciality, specialization,
   specialty, species, stamp, standard behavior, standard usage,
   standing custom, strain, stripe, strong point, style,
   stylistic analysis, stylistics, superficiality, system, tack,
   tactics, technicality, technique, tenor, the drill,
   the grand style, the how, the like of, the likes of,
   the plain style, the sublime, the way of, thing,
   time-honored practice, tone, total effect, tradition, tribe, trick,
   turn, twist, type, usage, use, variety, vein, view, viewpoint,
   vocation, way, way of life, ways, weakness, what is done, wise,
   wont, wonting