voluntary
— Noun
– English
～ composition (often improvised) for a solo instrument (especially solo organ) and not a regular part of a religious service or musical performance
voluntary muscle
— Noun
– English
～ striated muscle that can be controlled voluntarily
voluntary
— Noun
– English
～ (military) a person who freely enlists for service
voluntary
— Adjective
– English
～ of your own free will or design; done by choice; not forced or compelled; "man is a voluntary agent"; "participation was voluntary"; "voluntary manslaughter"; "voluntary generosity in times of disaster"; "voluntary social workers"; "a voluntary confession"
voluntary
— Adjective
– English
～ controlled by individual volition; "voluntary motions"; "voluntary muscles"