An attribute that is inadequate or deficient(noun)
WordNet. Princeton University. 2010.
Use "weak point" in a sentence
"Mal took his hands off him and got a file flash: Sammy railing against queers to Doc Lesnick, a weak point they could have played smart."
"It seems that the weak point in the sixteen onlays (partial crowns) I had two decades ago - the experience translated into my dental science fiction novel, Prostho Plus-is the cement."
"For these devourers, the weak point is where the two tails diverge."