Rhithymna or Rithymna (Greek: ) or Rhithymnia (Greek: ), was an ancient town on the island of Crete, Greece, which became a medieval bishopric under the name Retimo (as in Italian), which was suppressed and turned into a Latin Catholic titular see, which was later also suppressed.

Rhithymna or Rithymna (Greek: ) or Rhithymnia (Greek: ), was an ancient town on the island of Crete, Greece, which became a medieval bishopric under the name Retimo (as in Italian), which was suppressed and turned into a Latin Catholic titular see, which was later also suppressed.