label

noun1 of 2

a piece of paper or cloth that is attached to something and gives information about it

• “Each case was labeled with the type of liquid inside.”Tatoeba
• “The contents of the box are listed on the label.”Tatoeba

Sentences from Tatoeba show real usage. A word can have several meanings, so a sentence may use another one.

verb2 of 2

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.