Top definition. Musk. Though technically the name for the secretion of the male musk deer, musk is most often used as the name for the scent of arousal in both men and women, as actual musk is used in perfumes and colognes. Generally causes arousal for both genders, as it is a secondary sex characteristic.
These photoreceptors are called the rods and cones. Rods are called rods because under the microscope, they are shaped like, of all things, a rod. Finally, those pesky scientists named a structure for what it actually looks like as opposed to someone's unpronounceable last name!
Most fish see colors. As with people, the retina of a fishâs eye contains two types of cells: cones and rods. Cones are used for day vision and are the cells that discern color. Rods are used for night vision and cannot distinguish colors, although they can discern light. A rainbow of brightly colored fishing tackle.