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]