foreflap
/ˈfɒrflæp/Definitions
1. noun
A flap of fabric or skin at the front of something, such as a bird’s wing or a sail.
“The foreflap of the sail caused it to lose its aerodynamic properties.”
2. verb
To move or swing forward with a flap, especially in a forceful or uncontrolled manner.
“The bird foreflapped its wings to prepare for takeoff.”