A small pack or package; a little bundle or parcel

“Don't throw the crisp packet on the floor!”

Originally, a vessel employed by government to convey dispatches or mails; hence, a vessel employed in conveying dispatches, mails, passengers, and goods, and having fixed days of sailing; a mail boat. Packet boat, ship, vessel (Wikipedia).

A specimen envelope containing small, dried plants or containing parts of plants when attached to a larger sheet.

To make up into a packet or bundle.

To send in a packet or dispatch vessel.

To ply with a packet or dispatch boat.