Other forms: rejoined; rejoining; rejoins
To rejoin is to reunite or reconnect with, the way you rejoin your friends at the amusement park after they get off the terrifying rollercoaster.
When you go away from someone and then meet up again, you rejoin them. You can also rejoin a club or organization: "I quit band in sixth grade but decided to rejoin this year." In a courtroom, to rejoin is to respond to a plaintiff's statement — it's sometimes described as a reply to a reply. A less common meaning is "sharp, quick response." When one kindergartener calls another "stinky," she might rejoin, "I know you are, but what am I?"