weakness

A flaw or weak point.

Powerlessness revealed by an inability to act.

“in spite of their weakness the group remains active”

A penchant for something even though it might not be good for you.

“he has a weakness for chocolate”

The condition of being financially weak.

“the weakness of the dollar against the yen”

The property of lacking physical or mental strength; liability to failure under pressure or stress or strain.

“his weakness increased as he became older”

“the weakness of the span was overlooked until it collapsed”