Definition of velum
1 : a membrane or membranous part resembling a veil or curtain: such asa : soft palateb : an annular membrane projecting inward from the margin of the umbrella in some jellyfishes (as the hydromedusae)
2 : a swimming organ that is especially well developed in the later larval stages of many marine gastropods
Origin and Etymology of velum
borrowed from Latin vēlum “awning, curtain”; in sense 1a short for New Latin vēlum palātī or vēlum palātīnum, literally, “curtain of the palate” — more at 1veil
First Known Use: 1753
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