# turtles **URL:** \ **Category:** Factual Questions\ **Created:** [December 4, 2001, 3:50pm UTC](https://boards.straightdope.com/t/turtles/96844 "2001-12-04T15:50:10Z")\ **Posts on this page:** 11\ **Page:** 1
**Author:** ![vanilla](https://avatars.discourse-cdn.com/v4/letter/v/f19dbf/32.png) [@vanilla](https://boards.straightdope.com/u/vanilla)\ **Post date:** [December 4, 2001, 3:50pm UTC](https://boards.straightdope.com/t/turtles/96844/1 "2001-12-04T15:50:10Z")
My son wants to know the difference between a turtle and a tortoise. ---
**Author:** ![Popup](https://avatars.discourse-cdn.com/v4/letter/p/94ad74/32.png) [@Popup](https://boards.straightdope.com/u/Popup)\ **Post date:** [December 4, 2001, 4:00pm UTC](https://boards.straightdope.com/t/turtles/96844/2 "2001-12-04T16:00:33Z")
According to [Merriam-Webster](http://www.m-w.com/cgi-bin/dictionary?book=Dictionary&va=tortoise) Turtle is a broader term. Totroises are a subsets of turtles: > [@](#): > > Main Entry: **tor\*toise** > Pronunciation: 'tor-t&s > Function: noun > Etymology: Middle English tortu, tortuce, from Middle French tortue – more at TURTLE > Date: 14th century > 1 : **any of a family (Testudinidae) of terrestrial turtles; broadly : TURTLE** So, while in general the terms are used interchangeably, **tortoise** is more specific. ---
**Author:** ![Rue\_DeDay](https://avatars.discourse-cdn.com/v4/letter/r/41988e/32.png) [@Rue\_DeDay](https://boards.straightdope.com/u/Rue_DeDay)\ **Post date:** [December 4, 2001, 4:03pm UTC](https://boards.straightdope.com/t/turtles/96844/3 "2001-12-04T16:03:30Z")
Turtles swim. Tortoises don’t. Terrapins can if they want to, but don’t always. You know box turtles? They ain’t turtles at all. Nope. They’re terrapins. -Rue. ---
**Author:** ![Polycarp](https://avatars.discourse-cdn.com/v4/letter/p/82dd89/32.png) [@Polycarp](https://boards.straightdope.com/u/Polycarp)\ **Post date:** [December 4, 2001, 4:05pm UTC](https://boards.straightdope.com/t/turtles/96844/4 "2001-12-04T16:05:19Z")
It’s quite simple, Sterling. “Turtle” is used for all the reptiles with a “shell” (if you notice, he has skin joining two pieces, the upper one being called the “carapace” and the bottom one the “plastron”). Taxonomically, they’re Order Chelonia. It’s also used for the majority of those critters which live mostly in the water. A tortoise is a turtle (broad sense) which lives almost totally on land, rarely if ever entering the water. I think they represent one family in the turtle order, but I’m not certain and don’t have references on hand to check it. ---
**Author:** ![Darwins\_Finch](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/darwins_finch/32/20304_2.png) [@Darwins\_Finch](https://boards.straightdope.com/u/Darwins_Finch)\ **Post date:** [December 4, 2001, 5:10pm UTC](https://boards.straightdope.com/t/turtles/96844/5 "2001-12-04T17:10:34Z")
The Order Chelonia (which contains about 12 Families) contains all turtles, tortoises and terrapins. Tortoises belong to the Family Testudinae, while turtles occupy all the other 11 families. “Terrapin” is something of a generic term applied to large freshwater turtles. ---
**Author:** ![Tamerlane](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tamerlane/32/7602_2.png) [@Tamerlane](https://boards.straightdope.com/u/Tamerlane)\ **Post date:** [December 4, 2001, 5:16pm UTC](https://boards.straightdope.com/t/turtles/96844/6 "2001-12-04T17:16:19Z")
> [@](#): > > \*Originally posted by Polycarp \* > “Turtle” is used for all the reptiles with a “shell” (if you notice, he has skin joining two pieces, the upper one being called the “carapace” and the bottom one the “plastron”). Taxonomically, they’re Order Chelonia. Kee-rect. But most workers seem to prefer the ordinal name Testudines over Chelonia, these days 🙂 . Though I see people using both in weird fashions - i.e. quotes such as “…Chelonians ( Order Testudines )…” . I believe Chelonia is the older name and Testudines was once a family name, that has now been upgraded. > [@](#): > > A tortoise is a turtle (broad sense) which lives almost totally on land, rarely if ever entering the water. I think they represent one family in the turtle order, but I’m not certain and don’t have references on hand to check it. I think you were correct at one time, in fact I think Testudines may have been the name for the “tortoise family”. But apparently this has been tossed out. To quote from the fairly definitive Turtles of the World by Carl H. Ernst and Roger W. Barbour ( 1989, Smithsonian Instituition ): “All living shelled reptiles are turtles, but the terms tortoise and terrapin have also been applied, and these have different meanings in various parts of the world. Tortoise is best applied to terrestrial turtles. Terrapin is usually applied to edible, more or less aquatic, hard-shelled turtles.” - Tamerlane ---
**Author:** ![Tamerlane](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tamerlane/32/7602_2.png) [@Tamerlane](https://boards.straightdope.com/u/Tamerlane)\ **Post date:** [December 4, 2001, 5:25pm UTC](https://boards.straightdope.com/t/turtles/96844/7 "2001-12-04T17:25:11Z")
> [@](#): > > \*Originally posted by Darwin’s Finch \* > \*\*The Order Chelonia (which contains about 12 Families) contains all turtles, tortoises and terrapins. Tortoises belong to the Family Testudinae, while turtles occupy all the other 11 families. “Terrapin” is something of a generic term applied to large freshwater turtles. \*\* Okay, you made me go check a little more closely 🙂 . The tortoise family is indeed still Testudin **idae**. Mea Culpa. But Chelonia does seem to have fallen out of favor as the ordinal name. Well I was half-right, which is better than entirely wrong 😉 . ---
**Author:** ![Darwins\_Finch](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/darwins_finch/32/20304_2.png) [@Darwins\_Finch](https://boards.straightdope.com/u/Darwins_Finch)\ **Post date:** [December 4, 2001, 5:50pm UTC](https://boards.straightdope.com/t/turtles/96844/8 "2001-12-04T17:50:43Z")
> [@](#): > > _Originally posted by Tamerlane \* > **Okay, you made me go check a little more closely 🙂 . The tortoise family is indeed still Testudin** idae_\*. \*\* Ack. That’s what I get for being hard-of-seeing. Didn’t catch that extra “id” 🙂 Let’s try this again, using my preferred taxonomical method: cladistics! Turtles (again, including tortoises) are known as Testudines, as you mentioned, with tortoises occupying the clade known as Testudin **id** ae ( 😉 ) (which are most closely related to the various pond turtles). One of the characteristics of tortoises which sets them apart from the rest of turtledom is the fact that they are, of course, exclusively terrestrial. Essentially, all tortoises are turtles, but not all turtles are tortoises (say that ten times fast!). As **Tamerlane** alluded, “Chelonia” is largely only used in Linnaean circles. ---
**Author:** ![lissener](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lissener/32/6139_2.png) [@lissener](https://boards.straightdope.com/u/lissener)\ **Post date:** [December 4, 2001, 7:57pm UTC](https://boards.straightdope.com/t/turtles/96844/9 "2001-12-04T19:57:23Z")
Not sure where this comes into the whole picture, but tortoises are, AFAIK, exclusively vegetarian, and turtles/terrapins are carniverous to omniverous. ---
**Author:** ![Earl\_Snake-Hips\_Tucker](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/earl_snake-hips_tucker/32/3269_2.png) [@Earl\_Snake-Hips\_Tucker](https://boards.straightdope.com/u/Earl_Snake-Hips_Tucker)\ **Post date:** [December 4, 2001, 9:46pm UTC](https://boards.straightdope.com/t/turtles/96844/10 "2001-12-04T21:46:14Z")
“Turtle” is a corruption of the word “tortoise,” perpetrated by sailors. Since sailors generally saw “toroises” in the water, the distinction came to be made that “turtles” were seagoing and “tortoises” were terrestrial. BTW, the Bible makes references to turtles as in “the sound of the turtle” or “voice of the turtle,” which seems a little odd, but that is actually referring to doves, as in “turtle doves,” which has no tie-in with the reptilian types of turtles. “Turtle dove” is similar to “moo cow” or “hoot owl.” That is, an adjective describing the sound it makes, which to some resembles “Tur-tur.” Source–Isaac Asimov. ---
**Author:** ![vanilla](https://avatars.discourse-cdn.com/v4/letter/v/f19dbf/32.png) [@vanilla](https://boards.straightdope.com/u/vanilla)\ **Post date:** [December 5, 2001, 2:56pm UTC](https://boards.straightdope.com/t/turtles/96844/11 "2001-12-05T14:56:29Z")
Aw, thank you Polycarp. Sterling enjoyed seeing hisself referred to by name here. 🙂