also: ずい
voluntary; optional; at one's discretion
Describes something done by free choice, without compulsion. Common in formal contexts such as rules, contracts, and official notices.
Participation is voluntary, so please come at your convenience.
この書類の提出は随意とされています。
Submission of this document is considered optional.
Attendance at the information session is optional.
Please help yourself to drinks as you like.
Members may withdraw at their own discretion.
自由 means 'free' in the broad sense of liberty or freedom, while 随意 narrowly means being free to choose in one specific matter without obligation.
随時 focuses on flexible timing (as needed), while 随意 focuses on free choice or discretion (as one likes), so they overlap but stress different aspects.
随意 is a formal word meaning 'at one's own discretion,' usually about choices, whereas 自在 stresses skillful, unrestricted control or movement.
強制 means 'compulsory' or 'forced', the direct opposite of 随意's 'voluntary, at one's own discretion'.
随時 means 'at any time, as needed', while 随意 means 'voluntary, at one's discretion'; the two share the kanji 随 and are easily mixed up.
involuntary
voluntary; optional
voluntary muscle
private contract; negotiated contract; limited tender contract
Standard kanji spelling; high-frequency news and spec priority.
Irregular kana usage. Rarely encountered.
Compound of 随 (follow, comply) and 意 (mind, intention), literally 'following one's intention'. The meaning 'voluntary' or 'at one's discretion' is a natural extension.