Definitions for opsoninˈɒp sə nɪn

This page provides all possible meanings and translations of the word opsonin

Random House Webster's College Dictionary

op•so•ninˈɒp sə nɪn(n.)

  1. any of several constituents of blood serum, as an antibody or complement, that make invading microorganisms more susceptible to destruction by phagocytes.

    Category: Immunology

Origin of opsonin:

1900–05; < L opsōn(ium) victuals

op•son•icɒpˈsɒn ɪk(adj.)

Princeton's WordNet

  1. opsonin(noun)

    an antibody in blood serum that attaches to invading microorganisms and other antigens to make them more susceptible to the action of phagocytes


  1. opsonin(Noun)

    Any antibody that causes an invading species to be more susceptible to phagocytosis


  1. Opsonin

    An opsonin, is any molecule that enhances phagocytosis by marking an antigen for an immune response. However, the term is usually used in reference to molecules that act as a binding enhancer for the process of phagocytosis, especially antibodies, which coat the negatively charged molecules on the membrane. Molecules that activate the complement system are also considered opsonins. Phagocytic cells do not have an Fc receptor for IgM, making IgM ineffective in assisting phagocytosis. However, IgM is extremely efficient at activating complement and is, therefore, considered an opsonin. Opsonins can also refer to molecules that target a cell for destruction through the action of natural killer cells.


Find a translation for the opsonin definition in other languages:

Select another language:

Discuss these opsonin definitions with the community:


Use the citation below to add this definition to your bibliography:


"opsonin." STANDS4 LLC, 2014. Web. 20 Dec. 2014. <>.

Are we missing a good definition for opsonin?

The Web's Largest Resource for

Definitions & Translations

A Member Of The STANDS4 Network

Nearby & related entries:

Alternative searches for opsonin: