means The lightest and most abundant chemical element, a colorless flammable gas whose single proton and electron make it the simplest atom of all.

from Coined in the late 18th century by French chemist Lavoisier from Greek 'hydro-' (water) plus '-genes' (forming, born of) — literally 'water-maker,' because burning it produces water. The Greek root '-genes' is the same one hiding in 'genesis' and 'generate,' so the name quietly brands hydrogen as a parent of things.