NHK has learned the five proposed names that were not selected to represent Japan's next Imperial era.
The government announced on Monday that the next era, set to begin on May 1 when Crown Prince Naruhito ascends to the throne, will be known as "Reiwa."
Sources say "Eiko," "Kyuka," "Koshi," "Banna," and "Banpo" were also considered.
The government selected the six candidates from expert submissions. After discussing them with a special panel and the heads of both houses of the Diet on Monday, the government decided on "Reiwa" at a Cabinet meeting.
The six candidates were selected because the characters were easy to read and write, a criteria considered in Imperial era names.
"Eiko" was sourced from classical Japanese literature, while "Koshi" was derived from both Japanese and Chinese classics. They are "The Chronicles of Japan" and "The Classic of Poetry" from "The Four Books and Five Classics," a collection that contains the basic teachings of Confucius.
Chinese classics are included in the sources for "Kyuka," "Banna" and "Banpo."
The government says it will not disclose the name of the person who proposed "Reiwa," but it is believed to be Japanese literary scholar Susumu Nakanishi.
He specializes in "Manyoshu," the oldest existing anthology of Japanese poetry and source of the selected name.
Nakanishi is a Professor Emeritus at the International Research Center for Japanese Studies.