- reticulopodium
- reticulo-ruminal motility
- reticulospinal tract
- Reticulum
- retiform
- retighten
- retina
- retina cell
- retinaculum
- retinal
- retinal ganglion cell
- retinal hazard region
- retinal illumination mosaic
- retinal optical damage
- retinal pigment
- retinal prosthesis
- Retina Nebula
- retina recognition
- retinene
- retinitis pigmentosa
- retinoblast
- retinoblastoma
- retinoblastoma protein
- retinohypothalamic fibre
- retinoic acid