関節

1. Origins, structure, and basic meaning

• Structure: 関節 (かんせつ) is a body-part noun for a joint.
• Basic usage: 足首の関節を動かす makes the joint the object of movement; 指の関節がこわばる makes it the part becoming stiff.

2. Common pitfalls and similar expressions

• A joint and changes in mobility
  • 関節 is the body part where bones meet and movement occurs. It is commonly discussed in terms of range of motion, pain, or stiffness.