opaque sliding door
襖 centers on a specific type of opaque sliding door used in traditional Japanese architecture, often made of cloth or paper over a wooden frame.
襖 combines 衤 (clothing) with 奧 (deep, interior), suggesting a cloth-like covering for an interior opening. The exact historical development is uncertain, but the character likely reflects the material and function of the sliding door.
The left side 衤 (clothing) hints at the cloth or fabric covering, and the right side 奧 (interior) suggests a deep inner room. Picture a cloth-covered sliding door leading into a private interior space.
For オウ, imagine opening the sliding door and saying 'Oh!' as you enter the room: Oh -> オウ.