R

radial canal --> afferent canal
radial wall
rectilinear
recurrent flagellum
refractile body
reorganization band (= replication band)
reservoir
residual body
residuum
reticulate
reticulopodium
retractor fibers
retral process
rhabdocyst
rhabdos
rhoptry
ribbed wall
ring form
Rhizomastigida（根鞭毛虫類）
rootlet（小根支）
rosette
rostellum
rostral tube
rostrum