PRINCIPAL, a person or thing first, or chief in rank or importance, or, more widely, prominent, leading. The Lat. adj. principalis, first, chief, original, also princely, is formed from princeps, the first, chief, prince, from primus, first, and capere to hold. In Late Lat. principalis was used as a substitute for an overseer or superintendent, and also for the chief magistrate of a municipality (Symmachus, Ep. 9, i). It is a common title for the head of educational institutions, universities, colleges and schools. It is thus used of the director, of some of the heads of newer universities in England, e.g. London and Birmingham, always so in Scotland, and frequently combined with the vice-chancellorship. At the university of Oxford the name occurs twice as the title of the head of a college, viz. of Brasenose and Jesus. It was always used of the heads of halls, of which St Edmund Hall alone remains. It is also the designation used of the head of the newer theological or denominational colleges, and also of the women's colleges. At Cambridge it does not occur. In law, it is used in distinction from " accessory," for the person who actually commits the crime, " principal in the first degree," or who is present, aiding and abetting at the commission of the crime," principal in the second degree;" and also for the person for whom another acts by his authority (see PRINCIPAL AND AGENT below) . Finally as a shortened form of " principal sum," " principal money," etc., the term is used of the original sum lent or invested upon which interest is paid, and so, widely of any capital sum, as opposed to interest or income derived from it.
Note - this article incorporates content from Encyclopaedia Britannica, Eleventh Edition, (1910-1911)