The Latin word for ‘frog’ was rana, which the American Heritage Dictionary notes may have been of imitative origin; compare the way English speakers say rivet or ribbit for the sound a frog makes. Spanish has imitated Latin by carrying over rana as its own word for ‘frog,’ and zoology has followed suit by adopting Rana as the name for the genus that includes many familiar types of frogs. The Spanish rana spawned ranacuajo, now usually renacuajo, which means ‘tadpole.’ The word has added the slang sense ‘a runt,’ or as English says by switching to a different sort of little animal, ‘a shrimp.’ Spanish ranilla, literally ‘a small frog,’ can also mean what English has called a frog or frush, which is ‘the triangular prominence of the hoof, in the middle of the sole of the foot of the horse.’
One Latin diminutive of rana was ranula, literally ‘a little frog.’ The Romans extended the word metaphorically to mean ‘a small swelling on the tongue of cattle’ that must have looked to them like a little frog. The resemblance was apparently convincing enough that we’ve borrowed ránula/ranula in its figurative Latin sense; in addition, doctors use the term for ‘a cyst on the underside of the tongue caused by the blockage of a duct in a gland.’ Based on the location of such a cyst, two of the blood vessels on the underside of the human tongue have been named the vena ranina/ranine vein and the arteria ranina/ranine artery.
© 2011 Steven Schwartzman