What is meant by fuming nitric acid?

Fuming nitric acid is a highly concentrated and pure form of nitric acid that contains a high concentration of nitrogen dioxide gas. It is called "fuming" because it releases dense, white fumes of nitrogen dioxide gas when exposed to air. Fuming nitric acid is extremely corrosive and can cause severe burns and damage to skin, eyes, and respiratory system upon contact. It is commonly used in chemical synthesis and industrial processes.