In biology, caveolae (Latin for "little caves"; singular, caveola), which are a special type of lipid raft, are small (50–100 nanometer) invaginations of the plasma membrane in many vertebrate cell types, especially in endothelial cells and adipocytes.

In biology, caveolae (Latin for "little caves"; singular, caveola), which are a special type of lipid raft, are small (50–100 nanometer) invaginations of the plasma membrane in many vertebrate cell types, especially in endothelial cells and adipocytes.