The term vapor generally refers to a gaseous substance or mist that can be seen or felt. Some synonyms for this word include fog, mist, steam, smoke, and haze. Fog and mist are typically used to describe a dense, low-lying layer of vapor that can obscure vision and dampen surfaces. Steam is often associated with the vaporization of water, while smoke is a byproduct of combustion or burning. Haze, on the other hand, is a thin layer of vapor that can be seen in the air and can occur due to pollution or atmospheric conditions. Overall, synonyms for the word vapor depend on the context and nature of the substance being described.