the ratio of the maximum breadth to the maximum height of the orbital cavity multiplied by 100.
- Orbital muscle
orbital muscle n. A rudimentary nonstriated muscle, crossing the infraorbital groove and the sphenomaxillary fissure and united with the periosteum of the eye socket.
- Orbital plane
orbital plane n. The orbital surface of the maxilla that lies perpendicular to the Frankfort plane at the orbitale.
- Orbital process
orbital process n. The anterior and larger of the two processes at the upper extremity of the vertical plate of the palatine bone, articulating with the upper jawbone and the ethmoid and sphenoid bones.
noun, Physics. 1. . noun, Physics. 1. the quantum number that designates the orbital angular momentum of a particular quantum state of an electron in an atom and that assumes integral values from zero to one less than the value of the principal quantum number. azimuthal quantum number See under quantum number.