서로

each other; one another

Explanation

1. each other; one another
Toward each person who is one of two or more people who are related.

2. altogether
Together with or at the same time with one person who is one of two or more who are related.

3. against each other
If comparing two or more people or objects that are related.

Examples
서로 믿다
서로 비난하다
서로 원망하다

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