A device such as a plumb line that is used in making or marking a perpendicular line.
A line or plane that is perpendicular to another.
at or forming a right angle (to something).
Exactly upright; extending in a straight line toward the centre of the earth, etc.
Independent of or irrelevant to each other; orthogonal.
A flat, rectangular tool used to draw, cut or check the straightness of straight lines.
Living one's life opposing or eschewing the use of substances such as alcohol, tobacco, and drugs.