Here are some ways to understand the meaning:
* Lack of restraint: An ape is often seen as a symbol of wildness and impulsivity, lacking the control and social graces of humans.
* Foolishness: The idiom suggests the person is acting in a way that is silly or irrational, perhaps mimicking the physical actions of an ape.
* Disruptive behavior: Apes can be noisy and destructive, so this idiom might suggest that someone is being disruptive or causing problems.
Example:
"Don't act like an ape in the meeting! Calm down and let's discuss this rationally."
It's important to note that this idiom can be considered offensive as it compares humans to animals in a negative way. Therefore, it's best to use it cautiously or avoid it altogether, especially when talking about someone directly.