The word "定义" is formed through a logical conceptual fusion of its two component characters. The first character, "定" (dìng), carries the core meaning of "to fix", "to set", or "to determine". The second character, "义" (yì), represents "meaning", "significance", or "righteousness". When combined, they create a compound idea where "定" acts upon "义", effectively describing the act or result of fixing the meaning of something, hence arriving at the modern concept of "definition". It is a direct and efficient semantic construction where the relationship between the parts clearly conveys the whole.