noun (plural centuries)
1 Strictly speaking, centuries run from 01 to 100, meaning that the new century begins on the first day of the year 01 (i.e. 1 January 1901, 1 January 2001, etc.). In practice and in popular perception, however, the new century is held to begin when the significant digits in the date change, e.g. on 1 January 2000, when 1999 became 2000. 2 Since the 1st century ran from the year 1 to the year 100, the ordinal number (i.e. second, third, fourth, etc.) used to denote the century will always be one digit higher than the corresponding cardinal digit(s). Thus, 1066 is a date in the 11th century, 1542 is a date in the 16th century, and so on.