Nitric oxide (NO) Nitric oxide (NO), colourless, toxic gas that is formed by the oxidation of nitrogen. Though it has few industrial applications, nitric oxide performs important chemical signaling functions in humans and other animals and has various applications in medicine.
or British mollusc /ËmÉËlÉsk/. plural mollusks. Learner's definition of MOLLUSK. [count] biology. : any one of a large group of animals (such as snails and clams) that have a soft body without a backbone and that usually live in a shell.
Mollusks comprise a group of soft-bodied animals that includes snails, clams, and sea slugs. The most common characteristic of most mollusks is their shell. One of the largest groups, the snails, is renowned for their shells. Snails are univalves, which means they have one shell.And it is this shell that for many people is the epitome of the ocean.he most common characteristic of most mollusks is their shell. One of the largest groups, the snails, is renowned for their shells. Snails are univalves, which means they have one shell. And it is this shell that for many people is the epitome of the ocean.