labelling

To put a label (a ticket or sign) on (something).

“The shop assistant labeled all the products in the shop.”

(ditransitive) To give a label to (someone or something) in order to categorise that person or thing.

“He's been unfairly labeled as a cheat, although he's only ever cheated once.”

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.

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 vitro

A set of labels applied to the various objects in a system.

The introduction of a traceable chemical group (e.g., containing an isotope or a fluorescent dye) into a protein or other biomolecule of interest so it can be tracked or quantified during experimental analysis.