The Collaborative International Dictionary of English v.0.48:

Speciality \Spe`ci*al"i*ty\, n.; pl. Specialities. [See
   Special, and Specialty.]
   1. A particular or peculiar case; a particularity. --Sir M.
      Hale.
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   2. (Law) See Specialty, 3.
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   3. The special or peculiar mark or characteristic of a person
      or thing; that for which a person is specially
      distinguished; an object of special attention; a special
      occupation or object of attention; a specialty.
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            On these two general heads all other specialities
            are depedent.                         --Hooker.
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            Strive, while improving your one talent, to enrich
            your whole capital as a man. It is in this way that
            you escape from the wretched narrow-mindedness which
            is the characteristic of every one who cultivates
            his speciality.                       --Ld. Lytton.
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            We 'll say, instead, the inconsequent creature man,

            For that'a his speciality.            --Mrs.
                                                  Browning.
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            Think of this, sir, . . . remote from the impulses
            of passion, and apart from the specialities -- if I
            may use that strong remark -- of prejudice.
                                                  --Dickens.
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   4. An attribute or quality peculiar to a species.
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WordNet (r) 3.0 (2006):

speciality
    n 1: an asset of special worth or utility; "cooking is his
         forte" [syn: forte, strong suit, long suit, metier,
         specialty, speciality, strong point, strength]
         [ant: weak point]
    2: a distinguishing trait [syn: peculiarity, specialness,
       specialty, speciality, distinctiveness]
    3: the special line of work you have adopted as your career;
       "his specialization is gastroenterology" [syn:
       specialization, specialisation, specialty,
       speciality, specialism]

Moby Thesaurus II by Grady Ward, 1.0:

71 Moby Thesaurus words for "speciality":
   ability, accomplishment, adeptness, aptitude, area, art, baby, bag,
   bump, caliber, capability, capacity, concentration, craft,
   cup of tea, definiteness, dower, dowry, endowment, equipment,
   expertise, faculty, field, flair, forte, genius, gift, instinct,
   line, long suit, main interest, makings, manner, metier,
   natural endowment, natural gift, parts, pet subject,
   piece de resistance, potential, power, powers, pursuit,
   qualification, skill, special, special case, specialism,
   specialization, specialness, specialty, specificality,
   specificness, sphere, strength, strong flair, strong point, style,
   subject, talent, talents, technicality, the goods, the stuff,
   thing, trade, type, vocation, way, weakness, what it takes