an imperfection in a plan or theory or legal document that causes it to fail or that reduces its effectiveness
"The defense lawyer argued that a fatal flaw in the prosecution's case would lead to the dismissal of all charges."
A flake, fragment, or shiver.
"The sailor braced himself against a sharp windflaw that nearly capsized their small boat."
A sudden burst or gust of wind of short duration; windflaw.
In plain English: A flaw is a small mistake, weakness, or imperfection that makes something less perfect than it could be.
"The diamond was beautiful, but it had a small flaw inside that made it less valuable."
To add a flaw to, to make imperfect or defective.
"The careless repairman managed to flaw the vase by cracking its rim during the glue application."
In plain English: To flaw something means to ruin it by making small mistakes that make it imperfect.
"The bright sunlight began to flaw his once-perfect face with shadows and lines."
The word flaw comes from the Old Norse flaga, meaning a slab or flake of stone. It entered English via Middle English to describe any small imperfection or crack in an object.