In areal linguistics, Sinosphere (simplified Chinese: 汉字文化圈; traditional Chinese: 漢字文化圏; pinyin: Hànzì Wénhuà Quān; literally "Chinese character culture circle") refers to a grouping of countries and regions that are currently inhabited with a majority of Chinese population or were historically under Chinese cultural influence. The linguist James Matisoff coined the term "Sinosphere" in 1990, contrasting with the Indosphere, "I refer to the Chinese and Indian areas of linguistic / cultural influence in
The terms Chinese cultural sphere and
Chinese character cultural sphere are used interchangeably with
"Sinosphere" but have different denotations. Chinese cultural sphere
denotes a grouping of countries, regions, and people which have participated in
or been heavily influenced by the Culture of China, such as Tibet or Sichuan .
Countries such as Japan or Viet Nam which
historically or currently made some use of the Chinese writing system. However Vietnam has
departed significantly due to its wide adoption of Quốc ngữ, the romanized
Vietnamese alphabet. For Mainland Southeast Asia (MSEA) the term has been
glossed as "Sinosphere: a socio-political sphere of MSEA, subsuming those
countries, cultures, and languages that have historically come under influence
from the politics, culture, religion, and languages of China (notably Vietnam,
Southwestern China, northern parts of Laos, as well as most urban centers in
MSEA)."

The Sinosphere is generally unified by first written language ability in Chinese. This defines the unifying factor as the influence of traditional Chinese cultural beliefs, marked by Confucianist social and moral ethics, Taoist or Mahayana Buddhist religious beliefs, as embodied in text using Chinese characters (Hanzi in Chinese, Hán tự in Vietnamese, hanja in Korean and kanji in Japanese) whether within China proper or in a peripheral culture before it emerged from the dominance of the center.
Others indicators are Calligraphy (writing brush, writing ink, Rice paper and Inkstone), painting, sculpture, architecture (Ornament), clothing, music(musical instruments), cuisine (eating utensils, ingredients and cooking methods), logic (Confucianism), political system, appliance (furniture, art crafts) and so on, which generally believed to be originated in ancient China.