What did radical used to mean?

Historically, the term "radical" originated from the Latin Word "radicalis," meaning "pertaining to the root." In its early usage, it referred to fundamental changes or reforms, particularly in political or social contexts. Over time, it evolved to describe individuals or groups advocating for extreme or revolutionary changes in society, often challenging established norms and structures. Today, it still retains that connotation of advocating for profound transformation.