Each other is a common phrase used to describe the reciprocal relationship between two or more people or things. However, when writing or speaking, it may be useful to switch up the phrase with synonyms to avoid repetition. Some synonyms for "each other" include one another, reciprocally, mutual, jointly, and in unison. "One another" is commonly used in religious texts and literature, while "reciprocally" emphasizes a give-and-take nature of the relationship. "Mutual" highlights the shared connection between two parties, while "jointly" and "in unison" suggest a cooperative effort between multiple parties. Using synonyms can add variety to language and convey slightly different nuances in meaning.