noun, Physics, Chemistry.
See under (def 2a).
[awr-bi-tl] /ˈɔr bɪ tl/
of or relating to an .
of or denoting an orbit
(of a motorway or major road circuit) circling a large city
a region surrounding an atomic nucleus in which the probability distribution of the electrons is given by a wave function
an orbital road
1540s, with reference to eye sockets; 1839 with reference to heavenly bodies; from orbit (n.) + -al (1).
orbital or·bit·al (ôr’bĭ-tl)
Relating to an orbit.
A partial description of the quantum state of an electron (or other particle) orbiting the nucleus of an atom. Different orbitals have different shapes and orientations, depending on the energy of the electron, its angular momentum, and its magnetic number. Orbitals have no clear boundaries; the shape of an orbital, as depicted graphically, shows only the regions around the nucleus in which an electron has a relatively high probability of being found. No more than two electrons (each with opposite spin) can coexist in a single orbital because of the Pauli exclusion principle. See also probability wave, quantum number, shell..
noun, Chemistry. 1. a compound with molecule-size pores, as some sodium aluminum silicates, that chemically locks molecules in them: used in purification and separation processes. noun 1. (chem) a material that can absorb large amounts of certain compounds while not absorbing others and is thus suitable for use in separating mixtures
noun, Spectroscopy. 1. the spectrum of light emitted or absorbed by a species of molecule.
- Molecular surgery
molecular surgery n. A technique used to increase the drug susceptibility of tumor cells by introducing gene segments into such cells so as to alter their drug resistance.
- Molecular volume
noun 1. the volume occupied by one mole of a substance Also called molar volume