The word "萍水相逢" is formed by combining the noun "萍" (duckweed) with "水" (water) to set a scene, followed by the verb phrase "相逢" (to meet mutually), where "相" indicates reciprocity and "逢" means to encounter; this literal conjunction of elements creates a metaphor for accidental meetings, as duckweed floats and converges randomly on water.