タイ, ツイ, あいて, こた.える, そろ.い, つれあ.い, なら.ぶ, むか.う, つし
vis-a-vis, opposite, even, equal, versus, anti-, compare
JLPT3 G3 S7 F34
丵 is a depiction of a thick clump of tall grass. 對 is a variant of 丵 + 寸 hand/action indicator → lay clumps of grass out to dry, facing each other → *confront*; *face* → *opposite*; *a pair of*.
[Full Kanji Etymology List]