Brighton have signed goalkeeper David Stockdale from Fulham for an undisclosed fee.
Blackpool now have 10 players on their books after signing former Barnsley duo Jacob Mellis and Tomasz Cywka.
The former Chelsea man was signed by Derek McInnes on a free transfer in the summer having made the player captain of his former club St Johnstone.
However, Morris has made just five appearances this season and has mutually agreed to the cancellation of his contract.
The 34-year-old will now look for a new club.