相同 (xiāng tóng) is an adjective meaning 'identical', 'the same', or 'equal in every respect'. It combines 相 (xiāng), which here conveys mutual or reciprocal relationship, and 同 (tóng), meaning 'same' or 'alike'. Together, they emphasize complete sameness — not just similarity, but exact correspondence in nature, appearance, value, or function. It’s commonly used to compare two or more things, people, or concepts and assert their full equivalence.

This word appears frequently in formal and neutral contexts: academic writing, official documents, logical reasoning, and everyday comparisons where precision matters. Unlike similar terms like 一样 (yí yàng), which is more colloquial and often requires a copula (e.g., 是…一样), 相同 can directly modify nouns (e.g., 相同颜色) or follow 是/有/与 constructions (e.g., 与…相同). It carries no emotional connotation and is never used for approximate or subjective similarity.