## Principal axis

3 dicționare găsite pentru principal axis
Din dicționarul The Collaborative International Dictionary of English v.0.48 :
```
Principal \Prin"ci*pal\, a. [F., from L. principalis. See
Prince.]
1. Highest in rank, authority, character, importance, or
degree; most considerable or important; chief; main; as,
the principal officers of a Government; the principal men
of a state; the principal productions of a country; the
principal arguments in a case.
[1913 Webster]

Wisdom is the principal thing.        --Prov. iv. 7.
[1913 Webster]

2. Of or pertaining to a prince; princely. [A Latinism]
[Obs.] --Spenser.
[1913 Webster]

Principal axis. See Axis of a curve, under Axis.

Principal axes of a quadric (Geom.), three lines in which
the principal planes of the solid intersect two and two,
as in an ellipsoid.

Principal challenge. (Law) See under Challenge.

Principal plane. See Plane of projection
(a), under Plane.

Principal of a quadric (Geom.), three planes each of which
is at right angles to the other two, and bisects all
chords of the quadric perpendicular to the plane, as in an
ellipsoid.

Principal point (Persp.), the projection of the point of
sight upon the plane of projection.

Principal ray (Persp.), the line drawn through the point of
sight perpendicular to the perspective plane.

Principal section (Crystallog.), a plane passing through
the optical axis of a crystal.
[1913 Webster]

```
Din dicționarul The Collaborative International Dictionary of English v.0.48 :
```
Axis \Ax"is\, n.; pl. Axes. [L. axis axis, axle. See Axle.]
A straight line, real or imaginary, passing through a body,
on which it revolves, or may be supposed to revolve; a line
passing through a body or system around which the parts are
symmetrically arranged.
[1913 Webster]

2. (Math.) A straight line with respect to which the
different parts of a magnitude are symmetrically arranged;
as, the axis of a cylinder, i. e., the axis of a cone,
that is, the straight line joining the vertex and the
center of the base; the axis of a circle, any straight
line passing through the center.
[1913 Webster]

3. (Bot.) The stem; the central part, or longitudinal
support, on which organs or parts are arranged; the
central line of any body. --Gray.
[1913 Webster]

4. (Anat.)
(a) The second vertebra of the neck, or vertebra
dentata.
(b) Also used of the body only of the vertebra, which is
prolonged anteriorly within the foramen of the first
vertebra or atlas, so as to form the odontoid process
or peg which serves as a pivot for the atlas and head
to turn upon.
[1913 Webster]

5. (Crystallog.) One of several imaginary lines, assumed in
describing the position of the planes by which a crystal
is bounded.
[1913 Webster]

6. (Fine Arts) The primary or secondary central line of any
design.
[1913 Webster]

Anticlinal axis (Geol.), a line or ridge from which the
strata slope downward on the two opposite sides.

Synclinal axis, a line from which the strata slope upward
in opposite directions, so as to form a valley.

Axis cylinder (Anat.), the neuraxis or essential, central
substance of a nerve fiber; -- called also axis band,
axial fiber, and cylinder axis.

Axis in peritrochio, the wheel and axle, one of the
mechanical powers.

Axis of a curve (Geom.), a straight line which bisects a
system of parallel chords of a curve; called a principal
axis, when cutting them at right angles, in which case it
divides the curve into two symmetrical portions, as in the
parabola, which has one such axis, the ellipse, which has
two, or the circle, which has an infinite number. The two
axes of the ellipse are the major axis and the minor
axis, and the two axes of the hyperbola are the
transverse axis and the conjugate axis.

Axis of a lens, the straight line passing through its
center and perpendicular to its surfaces.

Axis of a microscope or Axis of a telescope, the straight
line with which coincide the axes of the several lenses
which compose it.

Axes of co["o]rdinates in a plane, two straight lines
intersecting each other, to which points are referred for
the purpose of determining their relative position: they
are either rectangular or oblique.

Axes of co["o]rdinates in space, the three straight lines
in which the co["o]rdinate planes intersect each other.

Axis of a balance, that line about which it turns.

Axis of oscillation, of a pendulum, a right line passing
through the center about which it vibrates, and
perpendicular to the plane of vibration.

Axis of polarization, the central line around which the
prismatic rings or curves are arranged. --Brewster.

Axis of revolution (Descriptive Geom.), a straight line
about which some line or plane is revolved, so that the
several points of the line or plane shall describe circles
with their centers in the fixed line, and their planes
perpendicular to it, the line describing a surface of
revolution, and the plane a solid of revolution.

Axis of symmetry (Geom.), any line in a plane figure which
divides the figure into two such parts that one part, when
folded over along the axis, shall coincide with the other
part.

Axis of the equator, ecliptic, horizon (or other circle
considered with reference to the sphere on which it lies),
the diameter of the sphere which is perpendicular to the
plane of the circle. --Hutton.

Axis of the Ionic capital (Arch.), a line passing
perpendicularly through the middle of the eye of the
volute.

Neutral axis (Mech.), the line of demarcation between the
horizontal elastic forces of tension and compression,
exerted by the fibers in any cross section of a girder.

Optic axis of a crystal, the direction in which a ray of
transmitted light suffers no double refraction. All
crystals, not of the isometric system, are either uniaxial
or biaxial.

Optic axis, Visual axis (Opt.), the straight line passing
through the center of the pupil, and perpendicular to the
surface of the eye.

Radical axis of two circles (Geom.), the straight line
perpendicular to the line joining their centers and such
that the tangents from any point of it to the two circles
shall be equal to each other.

Spiral axis (Arch.), the axis of a twisted column drawn
spirally in order to trace the circumvolutions without.

Axis of abscissas and Axis of ordinates. See Abscissa.
[1913 Webster]

```
Din dicționarul WordNet (r) 2.0 :
```
principal axis
n : a line that passes through the center of curvature of a lens
so that light is neither reflected nor refracted [syn: optic
axis]
```

Caută Principal axis cu Omnilexica

Acest site este bazat pe Lexica © 2004-2020 Lucian Velea

Poți promova cultura română în lume: Intră pe www.intercogito.ro și distribuie o cugetare românească într-o altă limbă!