label

1. (transitive) To put a label (a ticket or sign) on (something).Examples: "The shop assistant labeled all the products in the shop."Synonyms: tag, pricetransitive

2. (ditransitive) To give a label to (someone or something) in order to categorise that person or thing.Examples: "He's been unfairly labeled as a cheat, although he's only ever cheated once."; "A friend of mine who runs an intellectual magazine was grousing about his movie critic, complaining that though the fellow had liked The Godfather (page 58), he had neglected to label it clearly as a masterpiece."; "And the liberal blogosphere has long labeled Clinton part of the neoconservative wing, a conservative intellectual movement that supports an interventionist foreign policy."ditransitive

3. (biochemistry) To replace specific atoms by their isotope in order to track the presence or movement of this isotope through a reaction, metabolic pathway or cell.

4. (biochemistry) To add a detectable substance, either transiently or permanently, to a biological substance in order to track the presence of the label-substance combination either in situ or in vitroExamples: "They may be used to label and image a protein within tissue, to isolate cells on the basis of marker expression, or to physically capture a protein from a complex biological mixture...."