So, "arth" generally indicates something related to joints or articulation.
Here are some examples of words with the prefix "arth":
* Arthritis: Inflammation of a joint.
* Arthroscopy: A surgical procedure that examines the inside of a joint using a thin, flexible tube with a camera.
* Arthropod: An invertebrate animal with a segmented body, jointed limbs, and a hard exoskeleton (e.g., insects, spiders, crabs).
* Arthralgia: Joint pain.
It's important to note that the prefix "arth" can sometimes be spelled "arthro," as in "arthropod."