A fabrication; something made up (a false story, frame-up, or hoax), often created to mislead or incriminate someone.
彼は会社の金を横領したというでっち上げで告発された。
He was accused based on a fabricated charge that he embezzled company funds.
ネット上の噂をでっち上げて拡散するのは許されない。
It is unacceptable to fabricate and spread rumors online.
その証拠は後にでっち上げであったことが明らかになった。
The evidence later turned out to have been fabricated.
でっち上げ事件が発覚し、関係者が処分を受けた。
The fabricated case was exposed and the people involved were disciplined.