Step brothers are related through a marriage of one of their parents, but there are several synonyms that can be used to describe this unique relationship. 'Blended brothers' is one such term that is often used to describe a combination of siblings from different families. 'Joint brothers' is another synonym that is used to describe siblings who share one or more parents. 'Half-brothers' is another term that can be used to describe siblings who share one biological parent. Other synonyms for step brothers include 'extended brothers', 'non-blood brothers', 'fusion brothers', and 'reconstituted brothers'. Each of these terms highlight the complexity of step sibling relationships and the various ways in which they can come together.