to differentiate (an element, atom, etc.) by introducing a radioactive isotope or an isotope of unusual mass that may be readily traced through a complex process
to incorporate a labeled element into (a molecule, compound, material, etc.)
An item used to identify something or someone, as a small piece of paper or cloth attached to an article to designate its origin, owner, contents, use, or destination.
A descriptive term; an epithet.
A distinctive name or trademark identifying a product or manufacturer, especially a recording company.
Architecture A molding over a door or window; a dripstone.
Heraldry A figure in a field consisting of a narrow horizontal bar with several pendants.