# helium

/ˈhiɫiəm/ (US) · /hˈiːliəm/ (UK)

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

## Senses

### 1. chemical element

noun · CEFR B2 · Technical

a very light gas that has no color or smell and does not burn.

For teachers: the second-lightest chemical element, a colorless, odorless, and inert noble gas with atomic number 2.

- The party balloons were filled with helium so they would float to the ceiling.
- Helium is widely utilized in cryogenic research because its extremely low boiling point makes it an ideal coolant for superconducting magnets.

Usage: Uncountable when referring to the element in general; countable only when referring to specific isotopes or samples in a laboratory context.

## Examples

- The party balloons are filled with helium so they float.
- Scientists use liquid helium to cool the superconducting magnets in MRI machines to extremely low temperatures.
- As a byproduct of the fusion process within stars, helium represents a significant portion of cosmic matter, though it remains relatively scarce in the Earth's atmosphere due to its low density.

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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.