voluntary

a. 自動的、自願的、故意的、志願的、自發的

n. 自願行動、志願者、自由調

學術名詞

即興風琴曲：音樂
海號獨弦琴：音樂

英文釋義

(military) a person who freely enlists for service
composition (often improvised) for a solo instrument (especially solo organ) and not a regular part of a religious service or musical performance
of your own free will or design; done by choice; not forced or compelled
controlled by individual volition