The term "madcap" is an adjective used to describe someone who is wild, unconventional and impulsive in their behavior. This person tends to be energetic, lively and often engages in reckless or crazy activities that are typically considered out of the ordinary. The word comes from the term "mad" meaning insane or foolish, combined with "cap", which is a type of headgear traditionally worn by mad people in the past to indicate their unstable mental state. In essence, someone who behaves like a madcap is often seen as being eccentric and unpredictable, living life on the edge and not conforming to societal norms or expectations.