Synonyms/Hypernyms (Ordered by Estimated Frequency) of noun hydrogen

1 sense of hydrogen

Sense 1
hydrogen, H, atomic number 1 -- (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)
       => chemical element, element -- (any of the more than 100 known substances (of which 92 occur naturally) that cannot be separated into simpler substances and that singly or in combination constitute all matter)
       => gas -- (a fluid in the gaseous state having neither independent shape nor volume and being able to expand indefinitely)