Other forms: weaknesses
A weakness is a fault, or a lack of strength. A weakness in the argument, muscle weakness, know your weaknesses.
It is the opposite of strength in every sense — physical, structural and personal. In interviews, what is your greatest weakness is a standard and much-resented question. A weakness for something is a different thing and means a fondness that is hard to resist: a weakness for chocolate, a weakness for lost causes. That use is affectionate and carries no criticism at all. Note weaken, the verb, and weakly against weekly.
1nounweaknessA fault or lack of strength.
“The weakness in the roof was found by the third surveyor.”
2nounfondnessA fondness that is hard to resist.
“She has a weakness for anything with a cherry on it.”
Too few real examples of this word to estimate which sense is commonest.
weakness is a fault or lack.
Weak comes from Old Norse veikr, meaning pliant or bendable, replacing an Old English word. The -ness ending is the standard English way of turning an adjective into a state, and weakness is one of the oldest examples still in daily use.
Middle English
weyknesse
English, today
weakness
Built from
From Middle English weyknesse, replacing earlier Middle English wocnesse, wakenes, wacnesse (“weakness”), from Old English wācnes (“weakness”). Equivalent to weak + -ness.
Etymology from Wiktionary, CC BY-SA