What is Geniculum?

Legal Definition
A geniculum is a small genu, or angular knee-like structure. It is often used in anatomical nomenclature to designate a sharp knee-like bend in a small structure or organ.

For example, in the facial canal, the genicular ganglion is situated on the geniculum of the facial nerve, the point where the nerve changes its direction.
-- Wikipedia
Legal Definition
A degree of consanguinity. Spelman.
-- Black's Law Dictionary