When the Edo period entered into the latter half, it became common among court nobles to wear kosode in situations other than for times of rituals, and sode (sleeves) of kosode became luxurious and larger in peaceful times and furisode (a long sleeved type of kimono) was newly born and name 'kosode((literally means small sleeves) itself were not suitable to the reality of kimono, and the name kosode fell into disuse.
江戸時代も後期を過ぎると公家の間でも儀式以外では小袖を着るのが通例となり、また、小袖自体の袖も平和な時代の中で華美になり巨大化して振袖が誕生、そのため「小袖」と言う名称自体が実態に合わなくなり使われなくなってしまった。