velarium

noun

A large awning, especially one suspended over a Roman theater or amphitheater.

An awning which was often drawn over the roofless Roman theaters and amphitheaters to protect the spectators from rain or the sun. Also velum.

[NL.] In zoology, the marginal membrane of certain hydrozoans; the velum. See velum, 4.

The marginal membrane of certain medusæ belonging to the Discophora.

The marginal membrane of certain medusae belonging to the Discophora.