Dictionary Word of the Day

Here's the Dictionary.com Word of the Day:

agnate: a relative whose connection is traceable exclusively through males.

That's a new one to me and very much a genealogical word. Not sure how useful it is. How often do I need to refer to my dad's brothers or their sons? Or my dad's uncles on his father's side and their sons? We all share an X chromosome so it may be useful for genetic genealogy.