night blindness
C1Formal, Medical, Technical
Definition
Meaning
A condition of the eyes where vision is poor or absent in low-light conditions.
A medical condition (nyctalopia) resulting from a deficiency of vitamin A or certain eye diseases, impairing vision in darkness or dim light. Can be used metaphorically to describe an inability to understand or foresee something in a complex or obscure situation.
Linguistics
Semantic Notes
Primarily a medical/technical term. As a compound noun, it functions as an uncountable mass noun (e.g., 'suffers from night blindness'). The metaphorical use is rare and literary.
Dialectal Variation
British vs American Usage
Differences
No significant lexical differences. The term is standard in both varieties. 'Nyctalopia' is the more formal, clinical synonym used equally in both.
Connotations
Neutral medical condition in both. Slight tendency for 'night blindness' to be more common in general discourse, while 'nyctalopia' is strictly clinical.
Frequency
Equally low-frequency in general language, but standard within medical/ophthalmological contexts.
Vocabulary
Collocations
Grammar
Valency Patterns
[Subject] has/suffers from/experiences night blindness.Night blindness is caused by/treatable with...A symptom/complication of [disease] is night blindness.Vocabulary
Synonyms
Neutral
Weak
Vocabulary
Antonyms
Usage
Context Usage
Business
Extremely rare. Possibly in workplace safety discussions regarding vision requirements.
Academic
Common in medical, biological, and public health texts discussing nutrition or ocular diseases.
Everyday
Used when discussing a known medical condition or symptom. Not common in casual chat.
Technical
Standard term in ophthalmology, optometry, and general medicine.
Examples
By Part of Speech
adjective
British English
- The night-blind patient needed assistance after dusk.
- He described himself as night-blind following the diagnosis.
American English
- She is night-blind and avoids driving at night.
- Night-blind individuals often benefit from dietary supplements.
Examples
By CEFR Level
- He has night blindness and cannot see in the dark.
- A lack of vitamin A can cause night blindness in children.
- She doesn't drive at night because of her night blindness.
- The doctor explained that the patient's night blindness was a result of retinitis pigmentosa.
- Public health campaigns in the region aim to reduce night blindness through dietary education.
- Nyctalopia, or night blindness, is often an early indicator of a progressive retinal disorder.
- The study correlated the prevalence of night blindness with specific socioeconomic factors.
Learning
Memory Aids
Mnemonic
Think: 'Blind at NIGHT' – the word itself is descriptive. Remember it's the opposite of a cat's excellent night vision.
Conceptual Metaphor
IGNORANCE IS BLINDNESS (in extended use: 'He has a political night blindness, unable to see the dangers ahead.')
Watch out
Common Pitfalls
Translation Traps (for Russian speakers)
- Do not translate word-for-word as 'ночная слепота' without context, as it is the correct equivalent. No trap, but be aware it's a fixed medical term.
- The metaphorical use is far less established in English than the direct Russian metaphorical use might be.
Common Mistakes
- Using it as an adjective ('He is night-blind' is possible but less common than 'He has night blindness').
- Confusing it with 'colour blindness'.
- Treating it as a countable noun ('a night blindness').
Practice
Quiz
Which of the following is the most accurate definition of 'night blindness'?
FAQ
Frequently Asked Questions
No. Night blindness specifically refers to poor vision in low light or darkness. Daytime vision is often normal or near-normal.
It depends on the cause. If caused by a Vitamin A deficiency, it is often treatable and reversible with supplements. If caused by certain genetic eye diseases, it may be permanent.
They are synonyms. 'Nyctalopia' is the formal medical term derived from Greek, while 'night blindness' is the descriptive English term. They are used interchangeably in clinical settings.
Yes, 'night-blind' can function as a compound adjective. However, the more common phrasing is 'people with night blindness' or 'individuals suffering from night blindness'.