See Also: Principal(medicine)
Principal(finance)
principal boy(dictionary)
principal(dictionary)
Principal only (PO)(finance)
Principal-only (PO)(money)
Principal(money)
Principal(law)
Principal amount(finance)
Principal orders(finance)

principal (iou)



principal adjective, noun, & adverb. ME.
[Old & mod. French from Latin principalis first, chief, original, from princip-: see PRINCE, -AL1.]
A. adjective.
I.
First or highest in rank; most important, foremost; greatest. Also postpositive in titles, denoting senior status. ME.
Official Principal: see OFFICIAL noun 2. sheriff principal: see SHERIFF 1.
J. Thurber His principal and most successful business venture. N. Gordimer The principal source of information.
Belonging to the highest group or first rank; prominent, leading. Formerly freq. in superl. & (occas.) compar. ME.
H. James The master's principal productions. Times The survey..is..to contain five principal features.
Princely, royal. LME-L16.
Relatively or especially great or important; special, eminent. Now rare or obsolete. LME.
Of especially fine quality; excellent, choice. obsolete exc. Scot. LME.
II. spec.
Of money: constituting an original sum invested or lent; capital. ME.
Law. (Of a person) being the actual perpetrator of or directly responsible for a crime. ME-M16.
Of a document: original, not a copy. obsolete exc. Scot. LME.
Grammar. (Of a sentence or clause) superordinate to a dependent sentence or clause; (of a verb) superordinate to an auxiliary verb. L16.
Of a post, rafter, etc.: supporting the chief strain of a framework or building. L16.
Special collocations: principal axis Math. (a) the axis of a conic which passes through the foci, the transverse axis (opp. conjugate axis); (b) each of three chief lines of reference in a body or system. principal boy (an actress taking) the leading male role in a pantomime. principal challenge an objection, such as would lead to disqualification if proved, made against a jury or juror. principal-component(s) attrib. adjective (Statistics) designating a method of analysis which involves finding the linear combination of a set of variables that has maximum variance and removing its effect, repeating this successively. principal focus the focus of rays that impinge on a lens or spherical mirror parallel to its axis. principal girl (an actress taking) the leading female role in a pantomime. principal meridian Canad. a geographical meridian established by an authority as a meridian of reference for land surveying purposes; spec. the north-south line, 97 27' west, from which land in the prairies is surveyed. principal parts the parts of a (Latin or Greek) verb from which all the other parts can be deduced. principal point in perspective, the point where the principal ray meets the plane of delineation; in a lens or lens system, the point where the optic axis intersects the image plane. principal quantum number Physics the quantum number symbolized by n (see N, N 6b). principal ray in perspective, the straight line from the point of sight perpendicular to the plane of delineation. principal section Crystallography any section passing through the optic axis. principal stress Engineering each of the three purely tensile or compressive stresses acting in mutually perpendicular directions into which any combination of stresses acting at a point can be resolved.
b. noun.
I.
A person having the highest authority in an organization or institution; a chief, a head, a ruler; esp. the head of a school, college, or university. ME.
B. Head He resigned as principal of Swaneng Hill School.
b. In pl. Leading or prominent people in a community etc.; notables. LME-E17.
c. A fully qualified practitioner in some profession. LME.
British Medical Journal A random sample of 1824 principals in general practice was selected.
d. In Britain, a civil servant of the grade below Secretary. L19.
Law.
a. A person directly responsible for a crime. ME.
principal in the first degree: see FIRST adjective etc. principal in the second degree: see SECOND adjective.
b. A person who is the chief actor in or perpetrator of some action; spec. a person for whom another acts as agent or deputy. LME.
c. A person for whom another is surety for a debt etc. LME.
Either of the combatants in a duel. E18.
Any of the solo or leading performers in a play, opera, concert, etc. Also, the leading player in each section of an orchestra. L19.
P. G. Wodehouse Principals and chorus rehearsed together.
II.
A principal or main part, thing, etc. Now rare or obsolete exc. in phr. below. ME.
in principal arch. in the main, principally.
The best chattel belonging to an estate, bequeathed, or inherited by custom. obsolete exc. Hist. LME.
A main rafter supporting purlins; a main girder. LME.
A capital sum of money as distinguished from interest or income. LME.
a. An original document, drawing, painting, etc., as opp. to a copy. obsolete exc. Scot. L15.
b. An origin, a source. M16-E17.
An upright attachment used for holding candles on a hearse. M16-M19.
Falconry. Either of the two outermost primary feathers in each wing. Now rare. L16.
Music. An organ-stop sounding an octave above the diapason. E17.
III.
= PRINCIPLE. Now considered erron. M16.
principalness noun (rare) M16.
principalship noun the function or office of a principal, esp. the headship of a school, college, or university L16.