What is a half first cousin once removed?

Have you ever heard someone refer to themselves as a half first cousin once removed, and wondered what that meant? It sounds like a tricky family relationship to explain, but it’s actually quite simple. To understand this familial relationship, you first have to understand the basics of genealogy. Let’s take a look at how to explain “half first cousin once removed” in easy-to-understand terms.

What is a Cousin?

Cousins are two people who share one common ancestor. That ancestor could be a grandparent or great grandparent; in either case the two cousins will be descended from them, but not necessarily both by the same parent. For example, Person A and Person B could each have one parent who is the grandchild of the common ancestor. This would make them second cousins because they are two generations away from their common ancestor.

What Does “Once Removed” Mean?

When two people are described as being related “once removed”, it means that there is a difference in the number of generations between them and their most recent common ancestor. The person with fewer generations between them and the ancestor is considered to be “removed” from the other person. For example, if Person A has one generation separating them from their common ancestor while Person B has two generations separating them from their common ancestor, then Person B would be considered to be “once removed” from Person A.

What Does it Mean to Be Half First Cousins Once Removed?

Now that we know what cousins and “once removed” mean, we can put those concepts together and understand what half first cousins once removed means: two people who share one common great grandparent but through different grandparents are separated by one generation—one person has their great grandparent as a direct ancestor while the other has their great grandparent as an indirect ancestor (through another grandparent). This makes these two individuals half first cousins once removed.


Understanding family relationships can be confusing—especially when you start dealing with more distant relatives like half first cousins once removed! But with a basic understanding of genealogy terms like “cousins” and “once removed” you can easily explain these complex relationships in just a few words! Whether you’re researching your family tree or trying to get your relatives straightened out for holiday gatherings, now you know exactly what “half first cousin once removed” means!