nitro

1 of 2

adjective

ni·​tro ˈnī-(ˌ)trō How to pronounce nitro (audio)
: containing or being the monovalent group NO2 united through nitrogen

nitro

2 of 2

noun

plural nitros
: any of various nitrated products
specifically : nitroglycerin

Word History

Etymology

Adjective

nitr-

First Known Use

Adjective

1881, in the meaning defined above

Noun

1903, in the meaning defined above

Time Traveler
The first known use of nitro was in 1881

Rhymes for nitro

See All Rhymes for nitro

Browse Nearby Words

nitritoid
nitro
nitroamine
See all Nearby Words

Cite this Entry

“Nitro.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/nitro. Accessed 9 Sep. 2025.

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Medical Definition

nitro

1 of 2 adjective
ni·​tro ˈnī-(ˌ)trō How to pronounce nitro (audio)
: containing or being the monovalent group NO2 united through nitrogen

nitro

2 of 2 noun
plural nitros
: any of various nitrated products
specifically : nitroglycerin
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