Definitions of orbit:

• noun:   the (usually elliptical) path described by one celestial body in its revolution about another

  Example: "He plotted the orbit of the moon"

• noun:   the path of an electron around the nucleus of an atom
• noun:   the bony cavity in the skull containing the eyeball
• noun:   an area in which something acts or operates or has power or control

  Example: "In the political orbit of a world power"

• noun:   a particular environment or walk of life

  Example: "He's out of my orbit"

• verb:   move in an orbit

  Example: "The moon orbits around the Earth"