The term "blood relation" refers to a person who is related to you by blood, commonly known as a family member. However, there are several other synonyms that can be used to describe this type of relationship. One of the commonly used terms is "kin", which is used to describe a person's family or relatives. Another term that is often used is "family connection", which means someone who is related to you by blood or marriage. "Relative" and "kinsman" are also commonly used, with the latter used more commonly in a biblical context. Ultimately, these synonyms all refer to people who share a biological connection with you and are an important part of your family.