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Any of various proteins or glycoproteins that bind selectively to specific sugar moieties of glycoproteins and glycolipids on the surfaces of cells and are found in most organisms, especially plants. They are used to stimulate lymphocyte proliferation and to agglutinate red blood cells.
[Latinlēctus, past participle oflegere, to select; see SELECT + -IN (originally coined as a term for agglutinins of plant origin that were selective in binding only to cells of a certain human blood type).]
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:
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.