I had always assumed that turtle doves were named after turtles because of the tortoiseshell patterns on their wings. This is a natural hypothesis to anybody familiar with what a European turtle dove (Streptopelia turtur) looks like (see the picture below).
If you know what a European turtle dove sounds like, however, a different hypothesis might suggest itself. Its call is quite different from the “coo” of other familiar pigeons and doves. It’s a vibrating, purring sound, customarily transcribed as “turr-turr”, which is striking to the listener and easily distinguished from the call of any other bird.
The ancient Romans named the turtle dove the turtur due to its call, and this name was borrowed into Old English; it’s attested first in the Vespasian Psalter, from c. 825, and last in a book from 1649. However it was soon dissimilated to turtle, paralleling Spanish tórtola. This form is attested first in the Paris Psalter from c. 1000. It appears in the King James Bible, where the bird’s song is mentioned as a herald of summertime (European turtle doves winter in West Africa; the name “European turtle dove” is really quite parochial):
The flowers appear on the earth; the time of the singing of birds is come, and the voice of the turtle is heard in our land. (Song of Solomon 2:12)
The turtle dove is sadly less often heard as a herald of summertime in Europe today, as its population has declined greatly in recent times and it is classified as vulnerable by the IUCN. It’s not wholly understood why the decline has occurred but the loss of habitat (due to modern agricultural practices; turtle doves are farmland birds) and overhunting probably have something to do with it.
A few centuries after turtle, the compound turtle dove starts appearing in English texts, and today this has replaced turtle as the only current word for the species. It has also been applied to birds of other species, such as, in North America, Zenaida macroura, which ornithologists call the mourning dove. Mourning doves lack a tortoiseshell pattern on their wings, but of course, now we know that the name “turtle dove” has nothing to do with that. In appearance the European bird which mourning doves most closely resemble is really the collared dove (Streptopelia decaocto), but the collared dove actually wouldn’t have been known to the first English-speaking American colonists; collared doves were absent from most of Europe (except for the southeast) before their range started dramatically expanding in the middle 20th century (it’s still expanding—collared doves have recently arrived in North America, where they may end up competing with mourning doves).
So where does the name of the reptiles we call turtles today come from? Well, it’s a little mysterious. The classical Latin word for tortoises was testūdō (I don’t know if they had a different word for sea turtles), but in Late Latin there appears a synonym tortūca, perhaps a derivative of tortus ‘twisted’, from which most of the Romance words are derived (e.g. French tortue). English tortoise (first attested 1398, as tortuce, c. 1440 as tortu, 1484 as tortose) is said by the OED to be from the same source; the final -s may have come from the genitive -’s suffix by backformation from tortue’s shell. Note that the pronunciation with /-ɔjs/ in the second syllable is a spelling pronunciation; the original pronunciation, still current, is with schwa. Originally tortoise referred to all members of the order Testudines, the sea turtles (sea tortoises) of the family Cheloniidae included. The OED still gives this as the definition of tortoise but the entry is now probably obsolete. It’s therefore not implausible that the -oi- spelling is due to the influence of porpoise, from Latin porcopiscis 'pig-fish’, another word for a marine animal.
The word turtle is first attested in 1657 as a word for reptiles of the family Cheloniidae. The OED says that it is “apparently” a corruption of tortue influenced by turtle 'turtle dove’. However, it seems plausible enough to me that they were independently named after the turtle dove, due to the mottled pattern on their shells (most striking in sea turtles; tortoiseshell material was most commonly produced from the hawksbill sea turtle Eretmochelys imbricata) being reminiscent of a turtle dove’s wing colouration. In that case the turtle dove’s name would be connected to the tortoiseshell pattern on its wings—just not in the way I thought.
Since its coinage, turtle has competed with tortoise for the inclusion of reptiles of the order Chelonia in its denotation and it has tended to win its battles. The OED mentions that the sea turtles are often distinguished from the other reptiles of the order Testudines, and not considered to be tortoises, and also that the word turtle may be extended to refer to reptiles of the order Testudines that inhabit freshwater environments as well, although some zoologists, while still eschewing the word tortoise for these, prefer to use a third word, terrapin (from Algonquian). In modern English, apparently too recently for the OED to mention it, turtle has become the usual, zoologist-approved word for all reptiles of the order Testudines in North American usage, with the words tortoise and terrapin, if used at all, being regarded as words for particular varieties of turtle. In British usage a three-way distinction between (sea) turtles, (freshwater) terrapins and (land) turtles is still usually made.
I finished Español 3 (three years of Spanish classes) my sophomore year. I can (and do) yell at my family to shut up en Español from my secret blanket shell. They legitimately never find my blanket shell, I'm always hidden when I want to be, so they just hear someone yelling curses in Spanish from somewhere in the house- Turtle Anon™
We have to change your name to Fluent in Spanish Turtle Anon™ XD
M is for mata mata turtle, part of my ongoing unusual a-z series. Apparently mata mata means ‘kill kill’ in Spanish.
These turtles have incredibly long necks and as their look implies are aquatic ambush predators from South America, catching fish by opening their large mouths and creating a vacuum that sucks the unlucky fish or invertebrate in.