to play old harry with something
01
to make problems for something or have a negative effect on it
![to [play] Old Harry with {sth} definition and meaning](https://cdn.langeek.co/photo/44550/original/?type=jpeg "to [play] Old Harry with {sth} definition and meaning")
Idiom
Informal
例子
The careless team member played Old Harry with the project timeline, causing delays and confusion.
His habit of playing Old Harry with his finances led to a mountain of debt and financial troubles.
