Definition

1. Noun:
   • Nyctalopia: A medical condition characterized by the inability to see clearly in dim light or at night, commonly known as night blindness.

Usage Examples

• Noun:
  • Bệnh nhân được chẩn đoán mắc chứng dạ thị. (The patient was diagnosed with nyctalopia.)
  • Thiếu vitamin A có thể dẫn đến dạ thị. (A deficiency in vitamin A can lead to night blindness.)

Advanced Usage

• Medical Context: The term is used almost exclusively in formal medical, ophthalmological, or scientific writing and diagnosis in Vietnamese.
  • Dạ thị là một triệu chứng quan trọng cần được khám chuyên khoa mắt. (Nyctalopia is an important symptom that requires a specialist eye examination.)

Variants and Related Words

• Quáng gà: This is the common, everyday Vietnamese term for "night blindness." It is used much more frequently in general conversation than "dạ thị."
  • Ông ấy bị quáng gà nên không lái xe vào ban đêm. (He has night blindness so he doesn't drive at night.)
• Chứng mù đêm: Another descriptive synonym for the condition.

Synonyms

• Night blindness: The common English equivalent.
• Nyctalopia: The formal medical term in English.

Notes on Usage

• Formality: "Dạ thị" is a highly formal, Sino-Vietnamese (Hán-Việt) term. It is rarely used in everyday spoken Vietnamese, where "quáng gà" is standard.
• Field of Use: You will encounter "dạ thị" primarily in medical textbooks, scientific articles, or formal health communications.