Usage patterns
偽りを言うto tell a lie
偽りを暴くto expose a falsehood
The reporters exposed his falsehood.
〈事〉を偽りで固めるto build (a story) entirely on lies
His story was built entirely on lies.
偽りの〈物〉a fake/false ~
She showed a false smile.
Expressions
看板に偽りなしit's true to its name; it's just like it says on the box