China, as opposed to Japan and other islands / mainland China

China proper

the Chūgoku region (western part of Honshu comprising the prefectures of Okayama, Hiroshima, Yamaguchi, Tottori, and Shimane)

Chinese (any language spoken in China) / Chinese (class of languages) / Chinese (Mandarin)

China Standard Time

(humanities) sinology

the International Monetary Fund

Simplified Chinese (Chinese written using simplified characters)

Traditional Chinese (Chinese written using traditional characters)