SHM may stand for: Nanki–Shirahama Airport (IATA: SHM), in Wakayama, Japan Prefix for several shared memory functions in Unix-like systems (shmat, shmctl, etc.) Shek Mun station, Hong Kong, MTR station code Simple harmonic motion, in physics Somatic hypermutation, allowing immune system adaptation Structural health monitoring of engineering structures Supporting Healthy Marriage, US study Swedish House Mafia, a house music supergroup from Stockholm See also shm-reduplication, an example of reduplication in linguistics