Walter Frederick Morrison disc more cheaply. In 1955, he and Lu designed the Pluto Platter, the archetype of all modern flying discs. On January 23, 1957, they sold the rights for the Pluto Platter to the Wham-O toy company. Initially Wham-O continued to market the toy solely as the "Pluto Platter", but by June 1957 they also began using the name "Frisbee" after learning that college students in the Northeast were calling the Pluto Platter by that name. Morrison also invented several other products for Wham-O, but none were as successful as the Pluto Platter. Morrison and his wife, Lu Nay Morrison had
Pluto uses "Sao Diêm Vương", which was derived from the Chinese term 閻王 (Yánwáng), as "minh" is a homophone for the Sino-Vietnamese words for "dark" (冥) and "bright" (明)). Some Indian languages use the name Pluto, but others, such as Hindi, use the name of "Yama", the God of Death in Hindu and Buddhist mythology. Polynesian languages also tend to use the indigenous god of the underworld, as in Māori "Whiro". Once Pluto was found, its faintness and lack of a resolvable disc cast doubt on the idea that it was Lowell's Planet X. Estimates of Pluto's mass were revised downward