气味是人类嗅觉系统对散布于空气中的某些特定分子的感应。人们把使人愉快的气味称为香味，把使人不快的气味称为臭味。人类大概能识别1000种不同的气味。

气味分子进入鼻孔后，会与鼻腔上方的嗅觉细胞产生反应，产生的生物电波通过神经传到大脑。

An odor or odour or fragrance is caused by one or more volatilized chemical compounds, generally at a very low concentration, that humans or other animals perceive by the sense of olfaction. Odors are also commonly called scents, which can refer to both pleasant and unpleasant odors. The terms fragrance and aroma are used primarily by the food and cosmetic industry to describe a pleasant odor, and are sometimes used to refer to perfumes. In contrast, malodor, stench, reek, and stink are used specifically to describe unpleasant odor. The term smell (in its noun form) is used for both pleasant and unpleasant odors.