plural noun Si·al·i·dae \sīˈaləˌdē\

Definition of Sialidae

  1. :  a family of usually large insects (order Megaloptera) including the hellgrammite, alderflies, and related forms and having the hind wings broad at the base with their anal angle folding in plaits

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Origin and Etymology of sialidae

New Latin, from Sialis, type genus + -idae

Seen and Heard

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a rounded knoll or a ridge of ice

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