velum

plural vela · plural velums

1. A thin membrane resembling a veil or curtain.
   1. anatomyThe soft palate.
   2. biologyA thin membrane partially covering the cluster of sporangia near the leaf base in quillworts and their extinct relatives.
   3. biologyA veil-like membrane of immature mushrooms extending from the margin of the cap to the stem and is torn by growth, to reveal the gills.
   4. biologyA locomotory and feeding organ provided with cilia found in the larval stage of bivalves.
   5. biologyAn annular membrane, typically bordering a cavity, especially in certain molluscs, medusae, and other invertebrates.
   6. A delicate membrane found on certain protists.
2. climatologyAn accessory cloud resembling a veil extending over a large distance; normally associated with cumulus and cumulonimbus.
3. biologya thin coating or film of mucus or phlegm.