"Undesired" is a status of Treasures. See Desired and Treasure for details.
Desired
"Desired" and "Undesired" are statuses of Treasures. Each Treasure has three values: the Undesired value (marked in red), the Standard value (marked on a coin icon), and the Desired value (marked in green). By default, the Desired and Undesired value applies at Ports with the names indicated below the Desired and Undesired values on the Treasure card. At other Ports, the Standard value applies.
Certain Traits and other effects can override the location-based decision of which value applies. For example, the SAVVY Trait allows a Crew member to sell one item at the Desired value when you Visit a Port, no matter what the name of the Port is.