# crystalline

/ˈkɹɪstəˌɫaɪn/ (US) · /kɹˈɪstɐlˌaɪn/ (UK)

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

## Senses

### 1. made of crystals

adjective · CEFR B2 · Technical

made of or containing crystals.

For teachers: composed of or relating to crystals; having a regular, repeating three-dimensional molecular structure.

- The geologist found a crystalline rock that sparkled in the sun.
- The substance was identified as a crystalline solid, characterized by a highly ordered arrangement of atoms that resulted in sharp diffraction patterns.

### 2. clear and transparent

adjective · CEFR C1 · Literary

very clear and easy to see through, like high-quality glass.

For teachers: resembling crystal in being transparent, clear, or sparkling.

- The mountain stream had crystalline water that was freezing cold.
- The poet described the crystalline air of the high Alps, where every distant peak appeared with startling clarity against the blue sky.

### 3. pure or precise

adjective · CEFR C1 · Formal

very pure, or very clear and easy to understand.

For teachers: possessing a high degree of purity or intellectual clarity.

- The professor gave a crystalline explanation of the difficult theory.
- The author's crystalline prose allowed the complex philosophical arguments to be accessible even to those unfamiliar with the subject matter.

## Examples

- The mountain stream has crystalline water.
- The chemist examined the crystalline structure of the salt under a powerful microscope.
- The poet was celebrated for her crystalline prose, which managed to convey complex philosophical ideas with startling transparency and precision.

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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.