Any of various hard corals of the genus Madrepora or of the order Scleractinia (formerly Madreporaria).
[Italian madrepora : madre, mother (from Latin māter, mātr-; see māter- in the Appendix of Indo-European roots) + -pora (alteration of poro, tufa, pore, from Late Latin porus, passageway; see PORE2, or from Latin pōrus, calcareous stone, stalactite, from Greek pōros).]
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