Dome is an Australian colloquialism for followspot.
Theatres in Victorian times often had domed roofs, and within these there were removable panels in which a followspot could be used through, or just slots in the dome.
Therefore the followspots up in the dome were referred to as domes, and the followspot operators were called dome operators. This term has stuck, and is now commonly used in Australia to refer to any followspot operator - no matter what location they are operating from.
See an example of a dome here.
Theatres in Victorian times often had domed roofs, and within these there were removable panels in which a followspot could be used through, or just slots in the dome.
Therefore the followspots up in the dome were referred to as domes, and the followspot operators were called dome operators. This term has stuck, and is now commonly used in Australia to refer to any followspot operator - no matter what location they are operating from.
See an example of a dome here.