(This etymology is missing or incomplete. Please add to it, or discuss it at the Etymology scriptorium. Particularly: “kanji spellings are apparently ateji?”)
せいせい • (seisei) ←せいせい (seisei)?
(The following entries are uncreated: 正声, 生生, 西征, 声声, 征西, 清世, 清正, 清静, 盛世, 棲棲, 聖世, 精誠, 整正, 整斉, 井井, 正正, 青青, 凄凄, 済済, 萋萋, 菁菁, 整整, 韲韲.)