orb orb /ˈɔrb/

noun

1. () The ball-shaped capsule containing the vertebrate eye  ( eyeball , orb )
   the ball-shaped capsule containing the vertebrate eye
    The doctor used a special tool to examine the orb of the patient's eye.
   The doctor used a special tool to examine the orb of the patient's eye.
   
   
2. An object with a spherical shape  ( globe , orb , ball )
   an object with a spherical shape
    A ball of fire
   a ball of fire
   
   

verb

1. Move in an orbit  ( orb , revolve , orbit )
   move in an orbit
    The moon orbits around the Earth
   The moon orbits around the Earth
    The planets are orbiting the sun
   The planets are orbiting the sun
    Electrons orbit the nucleus
   electrons orbit the nucleus