time for doing something / period of time / season

important, significant

importance, consequence, significance

history / the study of history

age, era, period (of time) / the times, spirit of the age / antiquity / a time in one's life, one's days (in college etc.)

the Mesolithic

(historical or contemporary) any of several kingdoms, empires, or states of the Chinese people

the central part of a country, historically, commonly known as the capital city or the main region, where an emperor or other ruler resides / something within a country

Short for 中国地方 (Chūgoku chihō): the Chūgoku region of Japan

a surname