Definition of "SM"
SM
noun
plural SMs
(US, space science) Initialism of service module.
(music) Initialism of short meter.
(science fiction) Initialism of space marine.
(theater) Initialism of stage manager.
Initialism of sexual minority (“non-heterosexual”). (Also used attributively.)
Alternative form of S&M (“sadomasochism”)
proper noun
(physics) Initialism of Standard Model.