O'Neil Thompson is the third player in a week to leave the Bulls, the club have confirmed.
A statement on the official site says the midfielder wants to return to Jamaica, with Jamie Pitman saying: "O'Neil has been unsettled for some time and we thought it best for everyone if we came to this agreement. Everybody at United wishes him the very best for the future."
Thompson started six of the opening seven games, missing the other through injury, but then missed a month after a torrid display in the loss to Oxford. He made one further sub appearance at home to Port Vale.
The 27 year old was on loan from Barnsley, but he has also opted to end his Tykes contract after a disappointing time in English football.