stretch
暢 centers on the idea of stretching out smoothly and without obstruction, like something extending freely or flowing unimpeded.
暢 combines 申 (extend) with 昜 (bright/open), suggesting the idea of stretching out freely and smoothly.
The left side 申 looks like something extending outward, and the right side 昜 suggests openness and brightness. Together they create the image of stretching out smoothly under a wide, clear sky.
For チョウ, imagine a long, smooth stretch of road named Chou Avenue: Chou -> チョウ, and the road stretches out freely ahead.