0S (zero S) or 0-S may refer to: 0s, the period from January 1, AD 1 to December 31, AD 9, almost synonymous with the 1st decade (1–10). The period from January 1, AD 1 to December 31, AD 99, almost synonymous with the 1st century (1–100). The period from January 1, AD 1 to December 31, AD 999, almost synonymous with the 1st millennium (1–1000). 0S, 0°S, or zero degrees south, coordinate for the equator Zero S, a model of electric motorcycle 0 set, or zero set, a concept in mathematics 0 sum, or zero-sum, a theory in games and economics 0 sharp, also zero sharp or 0#, a concept in set theory 0 section, or zero section, a type of section in a Vector bundle See also 0s (disambiguation) OS (disambiguation) S0 (disambiguation)