- reindeer
- remora
- reptile
- resident
- retinaculum
- rhinoceros
- rhizocephalan
- ring-neck
- ripicolous
- reticula
- reticulum
- rhea
- rhizopod
- rice-bird
- ring ouzel
- ring-dove
- river-crocodile
- river-horse
- river-otter
- roach
- robin
- rochet
- rock-dove
- rock-fish
- rock-goat
- rock-pigeon
- rock-salmon
- rock-snake
- rodent
- roe
- roe-deer
- roebuck
- roo
- roller
- rook
- rorqual
- rotatoria
- round
- ruddock
- rumen
- rusa
- sablefish
- sagaciously
- ruff
- runner
- rucervus
- rudderfish
- sagacious
- saiga
- sail-fish
- saker
- salad-eel
- salangane
- rudd
- salmon
- salmon-coloured
- salmonet
- salmonid
- saltigrade
- sambar
- sambur
- sable
- saccus
- salad-fish
- salamander
- sarcelle
- saurel
- saury
- saw-shark
- scad
- scaly-anteater
- scaup
- scent-organ
- scoleces
- scollop
- scopate
- scopulate
- sand-fly
- sandfish
- sap-sucker
- sapajou
- sawn
- scallop
- scaphognathite
- scarab
- scent-gland
- schistosome
- sciurine
- scorpion
- scray
- screamer
- saw
- scale-winged
- scansorial
- scape
- scent-bag
- scombroid
- scoter
- sawfish
- sawyer