The Chinese word 同盟 (tóngméng) is a compound noun formed by combining two morphemes: 同 (tóng), meaning "same" or "together", and 盟 (méng), meaning "alliance" or "oath". Its formation follows a typical grammatical structure where the first character modifies or describes the second, creating the literal meaning of a "joint alliance" or "united pact". Historically rooted in the concept of swearing a collective oath, the term semantically evolved to denote any formal union for common action, such as a league or coalition, reflecting its syntactic construction as an endocentric compound where the core meaning resides in the concept of an "alliance" that is characterized by being "shared" or "unified", as seen in historical contexts like the 同盟会 (Revolutionary Alliance).