A coherent mass of pollen grains in a plant. They are the product of only one anther, but are transferred, during pollination, as a single unit. This is regularly seen in plants such as orchids and many species of milkweeds.
In general, being upside-down, supine, facing upward. In a biological context, the concept is commonly expressed with the adjectives "resupinate" or "non-resupinate."-- Wikipedia