Meaning of etherion | Babel Free
Definitions
A gas formerly believed to exist in air, initially identified by Charles F. Brush in 1898. He estimated that its density was one ten-thousandth of hydrogen.
countable, historical, uncountable
CEFR level
B2
Upper Intermediate
This word is part of the CEFR B2 vocabulary — upper intermediate level.
This word is part of the CEFR B2 vocabulary — upper intermediate level.