|an extraordinary or unusual thing, person, or event; an exceptional example or instance.|
|a calculus or concretion found in the stomach or intestines of certain animals, esp. ruminants, formerly reputed to be an effective remedy for poison.|
|the plural of sorus|
|sorus (sôr'əs) Pronunciation Key
Plural sori (sôr'ī)
in botany, brownish or yellowish cluster of spore-producing structures (sporangia) usually located on the lower surface of fern leaves. A sorus may be protected during development by a scale or flap of tissue called an indusium. In rust and smut fungi, a sorus is a spore mass produced on the leaf of an infected plant. Reproductive structures called sori also occur in various species of marine algae. See also spore.
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