barking mad
The phrase "barking mad" is an idiomatic expression typically used to describe someone who is behaving in a crazy or irrational manner. The term "barking" refers to the sound made by dogs when they bark excessively or incoherently. Hence, "barking mad" suggests that a person's behavior is so irrational, eccentric, or insane that it resembles the nonsensical barking of a dog.
English is confusing! Why do people say "Pardon my French" when they are speaking English? Because of idioms!
An idiom is a phrase or expression that usually presents a figurative, non-literal meaning attached to the phrase. Does that sound fun? It can be!
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