The term "washout" has several meanings, depending on its context.
In general terms, a washout is an area where water flows away or drains after heavy rain. It can also refer to something that fails completely, especially when it comes to expectations or plans. For example, if a project or idea is deemed a "washout," it means it has failed entirely and been abandoned.
In the context of weather, a washout refers specifically to a heavy downpour of rain that causes flooding or erosion. It can also refer to a roadway that becomes impassable due to water accumulation from rainfall.
Overall, "washout" is used to describe something that has been ruined, failed, or made useless by water.