equal, impartially, uniform, even
勻 centers on the idea of making things equal and uniform, distributing evenly and impartially without bias.
勻 is thought to combine 勹 (wrapping) with 二 (two), suggesting dividing something into two equal parts. The exact historical development is uncertain.
The outer 勹 wraps around two equal lines 二, like a container holding two identical portions. Picture dividing something evenly so each side gets the same amount.
For イン, imagine an innkeeper dividing rooms equally among guests: inn -> イン, and the innkeeper makes sure everything is fair and uniform.