removable blade - Richmond group
- retreat of valley sides
- retreat up the rise
- retreatal moraine
- retreated
- retreating
- retreating mining
- retreating sea
- retreating shrinkage
- retreating system
- retrenchment
- retrieval
- retrieving
- retrochoanitic
- retrofitting
- retrogradation
- retrograde alteration
- retrograde metamorphism
- retrogradiational parasequence set
- retrographic compound
- retrogression
- retrogressive erosion
- retrogressive metamorphism
- retrogressive movement
- retrosiphonate
- return
- return air
- return air course
- return air way
- return belt
- return bend
- return compartment
- return current
- return cut
- return flow
- return opening
- return pulley
- return pump station
- return shaft
- return slant
- return strand