- (botany) A thin membrane partially covering the cluster of sporangia near the leaf base in quillworts and their extinct relatives.
- (zoology) A circular membrane round the cap of medusa.
- (anatomy) The soft palate.
- (malacology) A locomotory and feeding organ provided with cilia found in the larval stage of bivalves.
- (meteorology) An accessory cloud resembling a veil extending over a large distance. Normally associated with cumulus and cumulonimbus.
- A thin membrane, resembling a veil, such as:
- (mycology) A 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.
- A delicate membrane found on certain protists.