Struggling to parse the following clue, so explanations as to how you arrived at the answer would be very helpful.
Onward movements from female monster beset by petrels. (12)
?R?G?E?S?O?S. The only word I can think of is "PROGRESSIONS" meaning onward movements. Ogre (monster) is also in the clue but how does "female", "beset" and "petrels" relate to the answer?