# crystal

/ˈkɹɪstəɫ/ (US) · /kɹˈɪstəl/ (UK)

Source: https://englishreference.com/word/crystal
Updated: 2026-08-15

## Senses

### 1. scientific solid

noun · CEFR B1 · Technical

a solid substance with a regular, repeating internal structure that creates a specific shape.

For teachers: a solid composed of an array of atoms or molecules possessing long-range order in a periodic three-dimensional pattern.

- Snowflakes are actually tiny ice crystals that form in the clouds.
- The geologist examined the quartz crystal under a microscope to identify the specific lattice structure of the mineral sample.

### 2. fine glassware

noun · CEFR B2

a very high-quality, clear glass used for expensive bowls or drinking glasses.

For teachers: a high-quality, highly refractive glass, traditionally containing lead oxide, used for decorative vessels.

- They brought out the fine crystal glasses for the wedding toast.
- The sunlight hit the crystal decanter on the sideboard, scattering prismatic colours across the dining room wall.

### 3. watch cover

noun · CEFR C1 · Technical

the clear glass or plastic cover that protects the face of a watch.

For teachers: the transparent cover, made of glass, synthetic sapphire, or plastic, that protects the dial of a timepiece.

- I accidentally scratched the crystal of my watch when I bumped into the wall.
- High-end diving watches typically feature a scratch-resistant sapphire crystal to ensure the dial remains legible under extreme conditions.

### 4. illegal drug

noun · CEFR C1 · Slang

a slang name for the illegal drug methamphetamine.

For teachers: a slang term for methamphetamine hydrochloride, particularly in its crystalline form.

- The police arrested the man for possession of crystal.
- The documentary explored the devastating impact that the production and sale of crystal had on rural communities over the last decade.

### 5. made of crystal

adjective · CEFR B1

made from crystal or high-quality glass.

For teachers: composed of or resembling crystal; often used to describe transparency or material composition.

- She wore a pair of crystal earrings that sparkled in the light.
- The chandelier was adorned with hundreds of crystal droplets that shimmered whenever the ballroom doors were opened.

### 6. very clear

adjective · CEFR B2

extremely clear and easy to see through or understand.

For teachers: possessing a high degree of clarity or transparency; often used figuratively for communication.

- The water in the mountain lake was crystal clear.
- The manager made it crystal clear that any further delays in the project would result in immediate disciplinary action.

Usage: Commonly used in the fixed phrase 'crystal clear'.

## Examples

- The salt formed small, white crystals on the table.
- She wore a necklace made of purple quartz crystals that caught the morning light.
- Geologists examined the jagged crystal formations within the cave to determine the mineral composition and age of the surrounding rock layers.

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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.