The word "遇到" is formed by combining the character "遇", which inherently means to meet or encounter, with "到", which denotes arrival or attainment. In this compound, "到" acts as a complement that emphasizes the completion or actualization of the action expressed by "遇", thereby refining the meaning to specifically indicate an encounter that has been realized or come to pass. This structural fusion creates a single lexical unit that conveys the idea of incidentally coming across something or someone, with "到" reinforcing the notion that the meeting is effectively occurring or has occurred.