1. root crop crop grown for its enlarged roots: e.g. beets
  2. root cap thimble-shaped mass of cells covering and protecting the growing tip of a root
  3. outcrop the part of a rock formation that appears above the surface
  4. rock outcrop the part of a rock formation that appears above the surface of the surrounding land
  5. rock group a band of musicians who play rock'n'roll music
  6. rock crab crab of eastern coast of North America
  7. radiocarbon a radioactive isotope of carbon
  8. root rot disease characterized by root decay; caused by various fungi
  9. stonecrop any of various northern temperate plants of the genus Sedum having fleshy leaves and red or yellow or white flowers
  10. root word the form of a word after all affixes are removed
  11. rap group a gathering of people holding a rap session
  12. riding crop a short whip with a thong at the end and a handle for opening gates
  13. podocarp any evergreen in the southern hemisphere of the genus Podocarpus having a pulpy fruit with one hard seed
  14. Red Cross an international organization that cares for the sick or wounded or homeless in wartime
  15. radiograph a photographic image produced on a radiosensitive surface by radiation other than visible light (especially by X-rays or gamma rays)
  16. ludicrous inviting ridicule
  17. radiography photography that uses other kinds of radiation than visible light
  18. Northrop United States biochemist (1891-1987)
  19. root for support or align oneself with
  20. white crappie a crappie that is white