n. 1. the sense of smell. 2. the process of smelling. Sensory cells in the mucous membrane that lines the nasal cavity are stimulated by the presence of chemical particles dissolved in the mucus. See nose. —olfactory adj.
n. the organ of olfaction, which also acts as an air passage that warms, moistens, and filters the air on its way to the lungs. The external nose is a triangular projection in the front of the face that is composed of cartilage and covered with skin. It leads to the nasal cavity (internal nose), which is lined with mucous membrane containing olfactory cells and is divided into two chambers (fossae) by the nasal septum. The lateral wall of each chamber is formed by the three scroll-shaped *nasal conchae, below each of which is a groovelike passage (meatus). The *paranasal sinuses open into these meatuses.... nose
(vomeronasal organ) a small blind sac in the wall of the nasal cavity. In humans it never develops properly and has no function, but in lower animals (e.g. snakes) it is one of the major organs of olfaction. [L. L. Jacobson (1783–1843), Danish anatomist]... organ of jacobson
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