atmospheric oxygen
The oxygen molecule O₂, as opposed to the element OThe oxygen molecule O₂ (diatomic oxygen), as opposed to the element O (monatomic oxygen).
Meaning
1 senses(uncountable)The oxygen molecule O₂ (diatomic oxygen), as opposed to the element O (monatomic oxygen).
Lessons for this word
1 lessons- A1Countable and uncountable nouns — Because it can be uncountable