castor
/kasˈtoɾ/ · B2 · noun · m
beaver
🦫 castor = cast + or: a beaver casts its dam of wood, gold-brown fur like 'or'
Sounds like English 'castor' as in castor oil, named from the beaver's castoreum gland. In Spanish, castor simply means beaver, so link the sound 'cas-TOR' with a dam-building animal that fells trees by gnawing.