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alternative pathway

n.
Immunology

The activation of complement by direct contact with polysaccharides located on the surface of bacteria or other pathogens. In contrast to the classical pathway, the alternative pathway is a nonspecific immune response that does not rely on the presence of antibodies.

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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