(chiefly in the plural) A quirk, idiosyncrasy, frailty, or mannerism; an unusual habit that is slightly strange or silly.
Try to look past his foibles and see the friendly fellow underneath.
A weakness or failing of character.
(fencing) Part of a sword between the middle and the point, weaker than the forte.
adjective
(obsolete) Weak; feeble.
The good Fencing-maſters, in France eſpecially, when they preſent a Foyle or Fleuret to their Scholars, tell him it hath two Parts, one of which he calleth the Fort or ſtrong, and the other the Foyble or weak […]