(usually clothing) Initialism of small (of the manufactured size).

(set theory) An axiomatic set theory, developed by logician George Boolos, in which several of the axioms of ZF are derivable as theorems.

(physics) subatomic particles with a spin (quantum angular momentum) of 0, predicted by supersymmetry; the bosonic equivalent of known fermions

(organic chemistry) secondary form

(business, often attributive) Initialism of sales and administration.

plural of A*

plural of A*

Possessive marker, indicating that an object belongs to the noun or noun phrase bearing the marker. / In the absence of a specified object, used to indicate “the house/place/establishment of”.

(sometimes proscribed) Used to form the plurals of numerals, letters, some abbreviations and some nouns, usually because the omission of an apostrophe would make the meaning unclear or ambiguous.

(symbols) Abbreviation of shilling, derived from the Latin solidus. / Abbreviation of season. / Abbreviation of south. / Abbreviation of substantive.