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nitrogen

n. uncountable
B2 Upper Intermediate US //ˈnaɪtɹədʒən// UK //nˈaɪtɹədʒən// ni·tro·gen

n. a gas that has no color or smell and makes up most of the air we breathe. It is essential for plants to grow and is often used in fertilizers.

n. a colorless, odorless, and tasteless chemical element that constitutes approximately 78 percent of Earth's atmosphere. It occurs as a diatomic gas and is a fundamental component of amino acids and proteins.


SIMPLE

Plants need nitrogen in the soil to grow strong and healthy.

CONTEXTUAL

Farmers often add nitrogen to their fields to ensure the crops have enough nutrients for a successful harvest.

COMPLEX

The industrial synthesis of ammonia from atmospheric nitrogen revolutionized global agriculture by providing a reliable source of synthetic fertilizer, though it also introduced significant environmental challenges.

Origin

Borrowed from French nitrogène (coined by French chemist and physician Jean-Antoine Chaptal in 1790). By surface analysis, nitro- + -gen. See also niter.

Usage

Uncountable when referring to the element or gas; occasionally countable in technical contexts referring to specific chemical compounds.

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