You can probably guess what this one means because you've probably used or heard a similar word quite often.
adjective 1. Of or like a sister or sisters
Etymology: mid 17th century: from Latin soror 'sister' + -al
Source: Oxford English Dictionary
So now, when someone wants to know what the feminine equivalent of fraternal is, you know. Also, a great way to use up all your annoying 1 point scrabble letters!
Erin Bedford, writer.