随時|ずいじzuiji[1]atamadaka (head-high)

1. adverbwhenever necessary; as needed; as required; as occasion demands
2. adverbat any time; at all times
   随時ずいじに退席たいせきしてもかまいません。↗

   You may leave your seat at will.

   なお、会社説明会かいしゃせつめいかい後ごでも、会社かいしゃ見学けんがくは随時ずいじ受け付うけつけております。↗

   Furthermore, even after the company information session, we sometimes hold company tours.

• Antonym定期ていきNeutralDone on a fixed term or at regular intervals — the opposite of handling something 「随時」, whenever the need arises.
• Antonym定時ていじNeutralRefers to a set, appointed time, as in 「定時退社」; contrasts with 「随時」, which puts no limit on when something is done.

Use 「随時」 for things done whenever needed, at no set time; choose 「定期」 for things done on a fixed cycle or term, and 「定時」 for things done at a set, scheduled time.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

1. 必要ひつようとするその時々ときどき。
2. 何時いつでも。