Skip to Content


Pronunciation: ka′rē-er


  1. A person who or animal that harbors a specific infectious agent in the absence of discernible clinical disease and serves as a potential source of infection.
  2. Any chemical capable of accepting an atom, radical, or subatomic particle from one compound, then passing it to another; cytochromes are electron carriers; homocysteine is a methyl carrier.
  3. A substance that, by having chemical properties closely related to or indistinguishable from those of a radioactive tracer, is thus able to carry the tracer through a precipitation or similar chemical procedure; the best carriers are the nonradioactive isotopes of the tracer in question.
  4. A large immunogen (usually a protein) that, when coupled to a hapten, facilitates an immune response to the hapten.
  5. A component of a membrane that causes the transfer of a substance from one side of the membrane to the other.
  6. The mobile phase in chromatography.
  7. A component of a biologic fluid that binds a ligand and transports that ligand to a ne wlocation.

See Also: label, tracer

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

© Copyright 2018 Wolters Kluwer. All Rights Reserved. Review date: Sep 19, 2016.