慣性

1. Origins, structure, and basic meaning

• Structure: 慣性(かんせい) means an object's tendency to maintain its state of rest or motion.
• Basic usage: It appears in explanations of motion, such as the body continuing forward when a car stops suddenly.

2. Common pitfalls and similar expressions

• The homophone 感性
  • 感性(かんせい) means sensitivity or the capacity to perceive and respond to things. 慣性 concerns physical motion, whereas 感性 concerns perception and feeling.