Definition of "frailty"

the limitations and restraints of civil government, and a legal constitution, may be defended, either from reason, which reflecting on the great frailty and corruption of human nature, teaches, that no man can safely be trusted with unlimited authority ;

1748, David Hume, Enquiries concerning the human understanding and concerning the principles of moral., London: Oxford University Press, published 1973, § 36, n. 1

For all their frailty at the back, Arsenal possessed genuine menace in attack and they carved through Chelsea with ease to restore parity nine minutes before half-time. Aaron Ramsey's pass was perfection and Gervinho took the unselfish option to set up Van Persie for a tap-in.

2011 October 29, Phil McNulty, “Chelsea 3 - 5 Arsenal”, in BBC Sport‎