# ultraviolet

/ˌəɫtɹəˈvaɪəɫɪt/ (US) · /ˌʊltɹɐvˈaɪələt/ (UK)

Source: https://englishreference.com/word/ultraviolet
Updated: 2026-08-27

## Senses

### 1. invisible light radiation

adjective · CEFR B2 · Technical

describes light that has a higher frequency than the violet light we can see.

For teachers: relating to electromagnetic radiation with wavelengths between approximately 10 and 400 nanometres, situated between visible light and X-rays.

- You should wear sunscreen to protect your skin from harmful ultraviolet rays.
- The telescope was designed to detect ultraviolet emissions from distant stars that are otherwise obscured by interstellar dust.

Usage: Often used as a compound adjective with 'light', 'radiation', or 'rays'.

### 2. UV radiation or light

noun · CEFR C1 · Technical

ultraviolet light or the part of the light spectrum that it belongs to.

For teachers: ultraviolet radiation or the region of the electromagnetic spectrum occupied by such radiation.

- The scientist used a special lamp that produces ultraviolet to find the hidden marks.
- The atmosphere absorbs the majority of the sun's extreme ultraviolet, preventing the most energetic radiation from reaching the planet's surface.

Usage: Typically functions as an uncountable noun when referring to the radiation itself.

## Examples

- You should wear sunscreen to protect your skin from ultraviolet rays.
- Bees can see patterns on flowers that are only visible in the ultraviolet spectrum, helping them find nectar more efficiently.
- The restoration team used ultraviolet light to reveal hidden layers of paint that had been covered up by previous artists centuries ago, providing a clearer picture of the original work.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.