mainland China; China proper
Refers to the geographical and political area of China excluding territories like Hong Kong, Macau, and Taiwan. 'China proper' is a historical term for the core Han Chinese regions.
Simplified Chinese characters are used in mainland China.
He was born and raised in mainland China.
中国 is the general term for China, which can include or exclude territories depending on context. 中国本土 specifically emphasizes the mainland area.
Compound of 中国 (China) and 本土 (mainland, home territory).