The most common and most likely answer to this crossword clue is the 5 letter word RADII
I've seen this crossword clue in The Times
R
A
D
I
I
More clues leading to the result RADII
- Run commercial on two lines
- Almost set one, maybe two bones?
- Awesome couple - more than one spoke
- Bones almost set, say, by head of institute
- Briefly set, I spoke several times
- Fantastic—two bones
- Arm reinforcements organising raid to capture island
- Â Broadcaster cut international lines
- Artist finally sculpted two bones
- Person who paints diameter and two lines in circle
Buddy explains!

The straight part
We know that "Bones" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case bones = radii.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does RADII mean?
RADII noun- The long bone in the forearm, on the side of the thumb.
- The lighter bone (or fused portion of bone) in the forelimb of an animal.
- One of the major veins of the insect wing, between the subcosta and the media; the vein running along the costal edge of the discal cell.
- A line segment between any point of a circle or sphere and its center.
- The length of this line segment.
- Anything resembling a radius, such as the spoke of a wheel, the movable arm of a sextant, or one of the radiating lines of a spider's web.