The word "签订" (qiāndìng) is a compound verb formed by combining two characters with related meanings: "签" (qiān), which means "to sign" (as with a signature or initials), and "订" (dìng), which means "to conclude," "to agree upon," or "to finalize." Together, they create a single term that denotes the formal act of signing and thereby finalizing a contract, treaty, or agreement. This formation follows a common pattern in Chinese where two synonymous or semantically linked characters are joined to express a more specific and complete action—in this case, the entire process of reaching and formally endorsing a binding pact.