chair
榻 centers on a piece of furniture for sitting: a chair or a low bench. The meaning is straightforward and concrete.
榻 combines 木 (wood) with a phonetic component that includes 羽 and 日. The exact historical development of the right side is uncertain, but the character likely originally referred to a wooden seat or couch.
The left side is 木 (tree/wood). Picture a simple wooden chair made from a tree: 榻 is a wooden chair.
For トウ, imagine sitting on a tall wooden chair that reaches up to the toe of a giant: toe -> トウ, and the chair is made of wood.