heart

1. Origins, structure, and basic meaning

• Structure: 心 has 4 strokes and the on-reading しん. 心 (こころ), meaning heart or mind, uses a kun-reading.
• Basic usage: 心 refers to feelings or a mental state; 心配 (しんぱい) refers to worry about a person or situation.

2. Common pitfalls and similar expressions

• A state of mind and worry
  • 心が温かくなった means that someone's heart was warmed. 心を落ち着かせた describes calming the mind by listening to music.
  • 弟を母が心配している means that the mother is worried about the younger brother. それほど心配しなくてよい means there is no need to worry that much.