Radii, e.g. Crossword Clue

 The answer to the crossword clue "Radii, e.g." is BONES.

A radius is a bone in the forearm that runs from the elbow to the wrist. It is one of two bones in the forearm, along with the ulna. The radius is responsible for rotating the forearm and hand.

The word "radii" is the plural of "radius." It is used to refer to two or more radii.

The crossword clue "Radii, e.g." is a bit of a trick question, because it asks for an example of a radius, but the answer is not actually a radius. The answer is "bones," because a radius is a type of bone.

This clue is a good example of how crossword clues can be challenging and require the solver to think outside the box.

I hope this helps!