foible

Concise Oxford English Dictionary © 2008 Oxford University Press:
foible /ˈfɔɪb(ə)l/

▶noun

• 1 a minor weakness or eccentricity.

• 2 Fencing the part of a sword blade from the middle to the point. Compare with forte1.

– origin C16 (as adj. in the sense ‘feeble’): from obs. Fr., in OFr. fieble (see feeble).