A "Leveler" is a tool used in construction and carpentry to determine whether a surface is horizontal (level) or vertical (plumb). It typically consists of a long, straight edge with a bubble vial in the center that indicates alignment. Levelers help ensure that structures, such as walls and floors, are built accurately, preventing future issues. In a broader context, the term "Leveler" can also refer to a historical movement in 17th-century England that advocated for social and political equality. This group sought to eliminate class distinctions and promote equal rights, influencing later democratic ideas and movements.