According to the stipulation by 'ebukuryo' (The garment code) of "Yoro ritsuryo code (the code promulgated in the Yoro period)," the ho (robe) of civil officers was called 'e (衣)' while ho of military officers was called 'ou (襖),' which seems to have been ketteki no ho.
奈良時代の『養老律令』の「衣服令」が定めるところによると、文官の袍が「衣」と呼ばれるのに対し、武官の袍は「襖」と呼ばれ、この「襖」が闕腋袍であったとみられる。