Corresponds to the anterior. (Costomediastinal) line of pleural reflection. 2. It is deeply notched in the left lung posterior. to 5th costal cartilage by the pericardium costal cartilage by the pericardium. and extends vertically downwards to form. Lingula.
Generally speaking, a principle is a rule, standard, or belief of one kind or another. As an adjective, principal means âmost importantâ, while a principal is â generally speaking â a person who is most important in a particular organization or group.
principle. 1  an accepted or professed rule of action or conduct: a person of good moral principles. 2  a fundamental, primary, or general law or truth from which others are derived: the principles of modern physics. 3  a fundamental doctrine or tenet; a distinctive ruling opinion: the principles of the Stoics.