Ribbons - Muses
The Muses ribbon appears when you work in the Muses pane of

Create/Use New: Creates a new Muse and adds it to the project. Opens the Create Muse window.
Delete: Deletes the selected Muse. You cannot delete a Muse that is still in use in the project. First, remove it from the project: clear its check box.

Retrain: Trains a Muse for the first time, or trains it again if it has been trained already. Retrain a Muse if, for example, you have new contents in the translation memories you trained it from. Opens the Train Muse window.