Definition & Meaning of "[laugh] like a drain"

What is the origin of the idiom "laugh like a drain" and when to use it?

The origin of the idiom "laugh like a drain" is unclear, but it is believed to have evolved as a humorous and whimsical expression to describe someone who is laughing heartily and loudly. The phrase combines the idea of laughter, which is often associated with joy and amusement, with the sound of water draining, which can be loud and continuous. It is used to emphasize the intensity of someone's laughter and the infectious nature of their amusement.