安心

1. Origins, structure, and basic meaning

• Structure: 安心 is read as あんしん and is a noun and する verb for relief or peace of mind after worry or uncertainty has been removed.
• Basic usage: A change into relief appears in 安心する, while the present reassured state appears in 安心です.

2. Common pitfalls and similar expressions

• Difference from 安全
  • 安全 is an objective condition of low danger; 安心 is the subjective feeling of being free from worry.
• Expressing the trigger
  • The information that produces relief can precede the verb, as in hearing a voice or learning that someone is safe.