Origin: Greek prefix hydro-
Hydrogen has 2 different meanings across 1 category:
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
"Hydrogen, the simplest and lightest element in the universe, burns with a pale blue flame as it reacts rapidly with oxygen."
The lightest chemical element (symbol H), with an atomic number of 1 and atomic weight of 1.00794.
"Hydrogen is the lightest chemical element on the periodic table, possessing an atomic number of 1."
In plain English: Hydrogen is the lightest and most common chemical element that makes up stars and fuels rockets.
"Hydrogen is the lightest element and makes up most of the universe's mass."
Usage: Hydrogen is the most abundant element in the universe, primarily found combined with oxygen to form water or within hydrocarbon fuels like natural gas. It serves as a clean-burning energy carrier when used directly rather than being burned alongside other elements.
The word hydrogen comes from French, where it was coined by chemists Louis-Bernard Guyton de Morveau and Antoine Lavoisier. It combines the prefix for "water" with a suffix meaning "producer," reflecting the fact that water is formed when hydrogen burns.