hydrogen
noun
Simple meaning
The lightest chemical element, with an atomic number of 1 and atomic weight of 1.008.
Pronunciation
Say it like this:
hydruhjuhnSay the bold part a little louder.
IPA pronunciation (US)
ˈhaɪdɹədʒən
This word is pronounced essentially the same in American and British English, so one transcription covers both.
IPA (International Phonetic Alphabet) is a standard way of writing speech sounds.
Definition
Everyday modern meanings first, grouped by part of speech.
noun
The lightest chemical element (symbol H), with an atomic number of 1 and atomic weight of 1.008.
Molecular hydrogen (H₂), a colourless, odourless and flammable gas at room temperature.
A nonmetallic univalent element that is normally a colorless and odorless highly flammable diatomic gas; the simplest and lightest and most abundant element in the universe
An atom of the element.
The isotope hydrogen-1 (protium) (symbol H or ¹H), contrasting with deuterium and tritium
A molecule of this molecular species
Word at a Glance
- Difficulty
- B1 · Intermediate (estimated)
- Frequency
- Common
- Typical Use
- Varies by meaning
Word Aura™
How this word commonly comes across.
Aura for this meaning
This meaning: The lightest chemical element (symbol H), with an atomic number of 1 and atomic weight of 1.008.
Used this way, hydrogen is a specialist word that usually carries little praise or criticism of its own. This is a scientific use: it names something precisely within a field of study, so it appears in research and teaching more than in conversation.
- Emotional tone
- Neutral
- Formality
- Specialist/technical
- Intensity
- Not strongly marked
- How common
- Specialized
- Connotation
- Clinical and technical
- Usage feel
- Technical and specialized
Where it naturally appears
- Science
- Academic writing
- Technical/specialist writing
Usage note
In general conversation this sense usually needs explaining — outside its field, people reach for a plainer word.
Word Aura describes common impressions, not a measurement. Tone changes with sentence, speaker, relationship and situation.
More ways to use hydrogen
- “Water is made of hydrogen and oxygen molecules.”
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Common Patterns and Combinations
How this word naturally appears with others.
Word Family
Related forms, grouped by how they connect.
Compound terms
Established multiword terms.
A colorless explosive liquid that is volatile and poisonous and foul-smelling.
Attack with a hydrogen bomb.
A chemical bond consisting of a hydrogen atom between two electronegative atoms (e.g., oxygen or nitrogen) with one side be a covalent bond and the other being an ionic bond.
A colorless gas that yields hydrobromic acid in solution with water.
A salt of carbonic acid (containing the anion HCO3) in which one hydrogen atom has been replaced.
A colorless corrosive gas (HCl).
Related Words
Connected to the same idea, not synonyms.
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Dictionary data from Wiktionary via the Free Dictionary API. Simple meanings, combinations and word intelligence are built from verified reference data, no AI is used to load this page.