sub·ter·res·tri·al 
(sŭb′tə-rĕstrē-əl)
(sŭb′tə-rĕstrē-əl)adj.
Subterranean; underground.
- Rodolfo Guglielmi.
- rodomontade
- Rodrigo Borgia.
- Rodrigo Díaz de Vivar.
- roe
- Roebling
- roebuck
- roe deer
- roentgen
- Roentgen
- roentgenium
- roentgenize
- roentgeno-
- roentgenogram
- roentgenograph
- roentgenographic
- roentgenographically
- roentgenography
- roentgenologic
- roentgenological
- roentgenologically
- roentgenologist
- roentgenology
- roentgenoscope
- roentgenoscopic