The sàn reading is the verb reading — the action of scattering, dispersing, ending. High-frequency compounds:
散步 (take a walk, the daily Chinese leisure ritual),
解散 (disband, dissolve),
分散 (scatter, distract),
扩散 (spread, diffuse),
散发 (emit, give off),
散心 (clear one's head). Read sàn whenever
散 is a transitive or intransitive verb.