The term co-wed refers to a marriage ceremony in which two couples get married at the same time by the same officiant. It is not widely used in English language and has only a few synonyms. One common synonym for co-wed is double wedding, which emphasizes the idea of two couples getting married together. Another similar term is joint wedding, which also implies the coming together of two couples to get married. Finally, the phrase concurrent wedding can be used to describe a co-wedding, emphasizing the simultaneous nature of the ceremony for both couples. While co-wed may not be a widely used term, these synonyms can help to express the same idea.