| altitude |
in geometry, a perpendicular line segment that extends from one vertex of a figure to the opposite edge or face, or the length of such a line segment; height. [1/4 definitions] |
| birefringence |
the splitting of a light wave into two perpendicular waves that have different speeds, as in some crystals. |
| Cartesian coordinates |
a pair of coordinates for locating a point on a plane by its distances from two intersecting, usu. perpendicular lines. [2 definitions] |
| dragonfly |
any of a large group of brightly colored insects with four long, veined, translucent wings usu. held perpendicular to a long, narrow body. |
| equatorial |
a telescope mounted on two axes, one parallel to and one perpendicular to the earth's axis of rotation. [1/3 definitions] |
| octant |
any of the eight parts into which three-dimensional space is divided by three mutually perpendicular planes. [1/4 definitions] |
| orthorhombic |
of or denoting a pattern of crystallization embodying three mutually perpendicular axes of different lengths. |
| perpendicular |
a perpendicular line or plane. [2/7 definitions] |
| plumb |
in a perpendicular or vertical line. [1/10 definitions] |
| precession |
the complex motion of a rotating body, such as a spinning top, when subjected to a disturbing force or torque that tends to move the axis of rotation in a direction perpendicular to the direction of the force, causing it generally to describe a cone. [1/3 definitions] |
| rake1 |
a tool consisting of a long handle and a row of tines extending perpendicular to it, used for gathering up debris or cultivating the ground. [1/12 definitions] |
| rake3 |
the angle at which a cutting or inscribing tool inclines from the perpendicular when applied to a surface. [1/4 definitions] |
| right angle |
an angle formed by the meeting of two perpendicular lines and measuring ninety degrees. |
| square |
forming a right angle; perpendicular. [1/24 definitions] |
| up-and-down |
vertical or perpendicular. [1/3 definitions] |
| vertical |
perpendicular to level ground; extending at right angles to the horizon; upright. [1/4 definitions] |
| vertical circle |
an imaginary circle on the celestial sphere that passes through the zenith and nadir and is thus perpendicular to the horizon. |