Because to and ryo are situated at the top of building and were its essential parts, the term "toryo" became the one that referred to an important person of organization like a nation and was also written in Chinese characters as '頭領' or '統領' (according to the description of "Nihonshoki" (Chronicles of Japan) for the fifty-first year of the Emperor Keiko (121), TAKENOUCHI no Sukune was described as '棟梁之臣' (Mune no machigimi) (a prime minister).
棟と梁は建物の最も高い部分にあり、かつ重要な部分であるため、転じて国家などの組織の重要な人物を指し、また「頭領」・「統領」という表記も用いられた（『日本書紀』景行天皇51年（121年）条において武内宿禰を「棟梁之臣」と表現している）。