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.
Full Definition of PRINCIPLE. 1. a: a comprehensive and fundamental law, doctrine, or assumption b (1) : a rule or code of conduct c: the laws or facts of nature underlying the working of an artificial device. 2. : a primary source: origin. 3.