tu·mor (tmər, ty-)
1. An abnormal growth of tissue resulting from uncontrolled, progressive multiplication of cells and serving no physiological function; a neoplasm.
2. A swollen part; a swelling: a plant tumor.
[Middle English tumour, from Latin tumor, from tumēre, to swell; see teuə- in the Appendix of Indo-European roots.]
tumor·al, tumor·ous adj.
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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:
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