(neologism) Those things that are planets; the state of being a planet.
1873, Enoch Fitch Burr, Pater Mundi: Or, Doctrine of Evolution., Holmes Noyes, pages 233-234One day our System in its progress through space neared these lost Children of the Mist....Such incorrigible vagrants, were enough to corrupt the habits of the staidest young family in Planetdom
2006 August 25, Ira Flatow, “Plutoâ€, Science Friday, National Public Radio...yesterday, its members voted to drop Pluto from the ranks of planetdom.
2006 August 26, Wendel Fendel, “Re: Pluto's a dwarfâ€, talk.origins, UsenetWhat did the Chisters say when Ceres was demoted from planetdom back in the 19th century?
2006 August 29, Manny Feld, “Re: solar systemâ€, talk.origins, UsenetBack in the 19-th century the asteroid Ceres was demoted from planetdom.
