n. pl. pe·nis·es or pe·nes (-nēz)
1. The male organ of copulation in higher vertebrates. In mammals, it also serves as the male organ of urinary excretion.
2. Any of various copulatory organs in males of lower animals.
[Latin pēnis; see pes- in the Appendix of Indo-European roots.]
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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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