nitric

You are most likely to meet "nitric" in chemistry. It usually describes something connected to nitric acid or appears in the name of a chemical, such as nitric oxide. In other words, it is a scientific label, not an everyday describing word.

Nitric acid is a strong and corrosive acid used in labs and industry, including the making of fertilizers and explosives. Because of that, the word often appears in serious technical contexts. You would not normally use "nitric" for ordinary objects or general situations.

The word "nitric" belongs mostly to the language of chemistry. In the clearest sense, it means "relating to nitric acid" and appears in set scientific names such as nitric acid and nitric oxide. It is not a broad everyday word for anything that contains nitrogen.

You will usually see it in discussions of acids, gases, laboratory work, manufacturing, or farming chemicals. Nitric acid (HNO3) is a strong, corrosive acid used in fertilizer production, metal treatment, and the manufacture of explosives and other chemicals. Because of these uses, the word often carries a technical and sometimes hazardous feeling.

The term also appears in older or more formal chemical naming, where it can point to a form with more oxygen than a related -ous form, as in the contrast between nitric and nitrous. Even so, most learners only need to remember the main idea: if something is called "nitric," it is usually being described in relation to nitric acid or a specific nitrogen-oxygen compound in chemistry.

So if the word appears in a text, you are probably reading something scientific rather than casual conversation. It helps name a narrow chemical idea, and that is where almost all of its real use lives.