noun

• 1Botany
  A plant in which the dormant buds are below the surface of the soil or submerged under water.

  Chamaephyte, hemicryptophyte, phanerophyte, and therophyte are the other categories in Raunkiaer's original classification of plant life forms.

• 2Biology
  A unicellular flagellate of the phylum Cryptophyta; a cryptomonad.