Radula n. : The chitinous ribbon bearing the teeth of mollusks; -- called also lingual ribbon, and tongue. See Odontophore.

Example:
What exactly does a Radula look like?

Taxonomy
radula, teeth, gastropods, lateral teeth, Formula, lateral tooth, ribbon, molluscs, arrangement, odontophore, tooth formula, species, early Cambrian, muscle, razor-sharp teeth, radular teeth, Food particles, middle teeth.

Defination from the web:
radula is unique to the molluscs, and is found in all clades of mollusks except for the bivalves. ... Predatory pulmonate land slugs such as the ghost slug use elongated razor-sharp teeth on the radula in order to seize and devour earthworms. ...