second in Chinese

Number-two; following after the first one with nothing between them. The ordinal number corresponding to the cardinal number two.

A unit of time historically and commonly defined as a sixtieth of a minute which the International System of Units more precisely defines as the duration of 9,192,631,770 periods of radiation corresponding to the transition between two hyperfine levels of caesium-133 in a ground state at a temperature of absolute zero and at rest.