Madreporian \Mad`re*po"ri*an\, Madreporic \Mad`re*po"ric\, a. (Zo["o]l.) Resembling, or pertaining to, the genus Madrepora.

Madreporic plate (Zo["o]l.), a perforated plate in echinoderms, through which water is admitted to the ambulacral tubes; -- called also madreporic tubercule.

Source: Webster's Revised Unabridged Dictionary (1913)