A damsel in distress
Definition 1 of 1
Pro Tip 1/3Cultural Origin
The phrase originates from medieval chivalric romances, where noble heroes rescue noblewomen from peril. 
Knights used to be the saviors of damsels in distress in old stories.
Pro Tip 2/3Gender Roles
The phrase often implies traditional gender roles, where men are rescuers and women are passive victims. 
He fancied himself a gallant knight saving the damsel in distress.
Pro Tip 3/3Stereotype Challenge
Modern use may challenge stereotypes, making the 'damsel' a strong character, or using the concept ironically. 
She laughed at the idea of being a damsel in distress; she could handle the situation herself.