c. 1300, "particular affection; special attachment or favor, partiality," from Old French especialte, more vernacular form of specialite (see speciality). Compare personalty/personality; realty/reality. From early 15c. as "unusual, or extraordinary thing; specialized branch of learning; peculiar quality, distinctive characteristic."

type of Italian stuffed turnover, a specialty of Naples, Italian, literally "trouser leg," so called for the resemblance.

"batter pudding made with black cherries," 1948, from French, from dialectal verb clafir "to fill." The dish is a specialty of the Limousin region.

often double whammy, "hex, evil eye," 1932, of unknown origin, popularized 1941 in Al Capp's comic strip "Li'l Abner," where it was the specialty of Evil-Eye Fleegle.

green, aromatic, olive oil-based pasta sauce, a Genoese specialty, 1937, from Italian pesto, contracted form of pestato, past participle of pestare "to pound, to crush," in reference to the crushed herbs and garlic in it, from Latin root of pestle.

"pastry case with a cooked, savory filling," a specialty of the Alsace-Lorraine region, 1949, from French quiche (1810), from Alsatian German Küche, diminutive of German Kuchen "cake" (see cake (n.)). The food became fashionable 1970s; became contemptible as indicative of wimpiness 1980s.

word-forming element; see -al (1) + -ity. Originally also in reduced form -alty, especially in words from French (mayoralty, etc.), hence the occasional doublet such as fealty/fidelity, realty/reality, specialty/speciality, loyalty/legality.

"type of sweet Italian bread," a specialty of the Lombardy region, made with candied fruit, etc., popular at holidays, by 1904, from Milanese dialect panatton (itself attested as an Italian word in English by 1862), a variant, probably augmentative, form of Italian pane "bread," from Latin panis "bread," from PIE root *pa- "to feed." 

"one who avoids company," 1946; see lone. Apparently first in U.S. baseball slang:

Ted [Williams] is likable enough in spite of his obsession with his specialty. He is something of a "loner," and he refuses to pal around with his teammates in off hours, but in the clubhouse he does his share of the talking. [Life magazine, Sept. 23, 1946]

c. 1300, "act or operation of burning," from Old English bryne, from the same source as burn (v.). Until mid-16c. the usual spelling was brenne. Meaning "mark or injury made by burning" is from 1520s. Slow burn is attested by 1938, in reference to U.S. movie actor Edgar Kennedy (1890-1948), who made it his specialty.