What is the origin of the idiom "keep a lid on something" and when to use it?
The idiomatic phrase "keep a lid on something" has its origins in the United States in the late 19th/early 20th century, deriving from the literal notion of securely fastening a tight-fitting lid onto a container to prevent its contents from spilling out, which then developed figuratively into referring to keeping information contained or suppressed, as evidenced by some early newspaper citations from the late 1800s discussing keeping secrets or scandals tightly guarded. It is frequently used in political, legal, and workplace settings to describe efforts to prevent damaging leaks, skeletons in the closet from being aired out, or potential scandals from emerging.