/ Dictionary / Index O orbital quantum number: Meaning and Definition of Find definitions for: or'bital quan'tum num"ber Pronunciation: [key] — Physics. Physics. See Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. orbital index orbital sander Related Content Daily Word Quiz: pugilist Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language