• 回転かいてん — rotation, spinning
• 一回いっかい — one time
• 挽回ばんかい — recovery, redemption, making up for
• 回収かいしゅう — collection, retrieval, recovery (e.g. test papers, scattered items)
• 回線かいせん — telephone/communication line; circuit
• 回答かいとう — answer, response
• 回路かいろ — (electrical) circuit

This kanji symbolizes something circling or looping around—think of water swirling. It’s often used for physical rotation and abstract repetition (like “one time” or “again”).

ドアが回まわっています。
The door is spinning.

もう一回いっかい、お願ねがいします。
One more time, please.