The word 来往 is formed by combining two opposite directional actions: 来 (lái), meaning "to come", and 往 (wǎng), meaning "to go". By pairing these two contrary movements, the compound naturally evokes the idea of reciprocal motion back and forth between points. This creates a unified concept of interaction, exchange, or mutual visitation, capturing the continuous cycle of coming and going rather than a single, one-way action.