Mutual
Each Other, Reciprocal, Together
noun
Despite it looking like an adjective, this is the noun version of the kanji, making it mutual. It also means each other and reciprocal and together, too.
Let's help each other. Maybe if we work together we can get rid of this tagger (たが) tagging graffiti all over our neighborhood.
あの二人は、「どうぞお座りください」とお互いに席の譲り合いをしたんだ。
The two people said, "Here, take my seat," to each other.