# flask

/ˈfɫæsk/ (US) · /flˈɑːsk/ (UK) · CEFR B2 · Noun

Source: https://englishreference.com/word/flask
Updated: 2026-05-07

## Definition

a container used to hold liquids. In a kitchen, it often keeps drinks hot or cold; in a science lab, it is a glass bottle with a special shape for experiments.

For teachers: a container with a narrow neck used to hold liquids, typically made of glass for laboratory use or insulated metal for maintaining temperature.

## Examples

- He poured hot coffee from his flask into a cup.
- The chemist carefully swirled the blue liquid inside the glass flask to ensure the chemicals mixed thoroughly.
- To maintain the integrity of the sample, the researcher transferred the solution into a vacuum-insulated flask designed to prevent any thermal exchange with the external environment.

## Usage notes

- In British English, often refers specifically to a vacuum flask (Thermos); in American English, frequently refers to a small, flat container for alcohol.

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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.