To keep back; to retain.

“We reserve the right to make modifications.”

To keep in store for future or special use.

“This cake is reserved for the guests!”

To book in advance; to make a reservation.

“I reserved a table for us at the best restaurant in town.”

Slow to reveal emotion or opinions.

“He was a quiet, reserved person.”

Set aside for a particular person or purpose.

“I'm sorry, sir, but these are reserved seats.”