- 1/60 of a minute; the basic unit of time adopted under the Systeme International d'Unites
同义词：second, sec, s
- 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)
同义词：sulfur, S, sulphur, atomic number 16
- the cardinal compass point that is at 180 degrees
同义词：south, due south, southward, S
- a unit of conductance equal to the reciprocal of an ohm
同义词：mho, siemens, reciprocal ohm, S
- the 19th letter of the Roman alphabet
同义词：S, letter s
- (thermodynamics) a thermodynamic quantity representing the amount of energy in a system that is no longer available for doing mechanical work
同义词：randomness, entropy, S
