The word 誓言 is formed through the conceptual fusion of its two component characters: 誓, which carries the meaning of a pledge or solemn vow, and 言, which signifies speech or spoken words. By combining them, the compound visually and semantically depicts "spoken words of a vow", where 言 specifies the medium (speech) through which the abstract commitment of 誓 is concretely expressed. This creates a new, unified concept stronger than either part alone, a solemn, spoken pledge or oath.