S

(noun) 1/60 of a minute; the basic unit of time adopted under the Systeme International d'Unites. Synonyms: second, sec, s.

(noun) an abundant tasteless odorless multivalent nonmetallic element; best known in yellow crystals; occurs in many sulphide and sulphate minerals and even in native form (especially in volcanic regions). Synonyms: sulfur, sulphur, atomic number 16.

(noun) the cardinal compass point that is at 180 degrees. Synonyms: south, due south, southward.

(noun) a unit of conductance equal to the reciprocal of an ohm. Synonyms: mho, siemens, reciprocal ohm.

(noun) the 19th letter of the Roman alphabet. Synonyms: s.

(noun) (thermodynamics) a thermodynamic quantity representing the amount of energy in a system that is no longer available for doing mechanical work. Synonyms: randomness, entropy. Examples: "Entropy increases as matter and energy in the universe degrade to an ultimate state of inert uniformity."