# Ass Bone **URL:** \ **Category:** Factual Questions\ **Created:** [April 6, 2000, 2:31am UTC](https://boards.straightdope.com/t/ass-bone/9877 "2000-04-06T02:31:00Z")\ **Posts on this page:** 14\ **Page:** 1
**Author:** ![inertia](https://avatars.discourse-cdn.com/v4/letter/i/d07c76/32.png) [@inertia](https://boards.straightdope.com/u/inertia)\ **Post date:** [April 6, 2000, 2:31am UTC](https://boards.straightdope.com/t/ass-bone/9877/1 "2000-04-06T02:31:00Z")
What is the technical name for the bone in your ass? I’ve never heard it called anything other than “ass bone”? I think it might be the back of the pelvis, but I’m no veteranarian. ---
**Author:** ![KarlGauss](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/karlgauss/32/3713_2.png) [@KarlGauss](https://boards.straightdope.com/u/KarlGauss)\ **Post date:** [April 6, 2000, 2:38am UTC](https://boards.straightdope.com/t/ass-bone/9877/2 "2000-04-06T02:38:00Z")
The bone just above your asshole is the coccyx. Above that, the sacrum. On either side, but higher than the coccyx, are the ischium and the ilium. ---
**Author:** ![inertia](https://avatars.discourse-cdn.com/v4/letter/i/d07c76/32.png) [@inertia](https://boards.straightdope.com/u/inertia)\ **Post date:** [April 6, 2000, 2:49am UTC](https://boards.straightdope.com/t/ass-bone/9877/3 "2000-04-06T02:49:00Z")
Are the ischium and the ilium the really pointy ones? ---
**Author:** ![KarlGauss](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/karlgauss/32/3713_2.png) [@KarlGauss](https://boards.straightdope.com/u/KarlGauss)\ **Post date:** [April 6, 2000, 3:01am UTC](https://boards.straightdope.com/t/ass-bone/9877/4 "2000-04-06T03:01:00Z")
I’m not exactly sure that I follow, but the coccyx could be considered pointy, sort of like a pine cone or rapidly tapering stack of discs. The sacrum is also pointy, like a triangle (with one vertex pointing to the floor if you’re standing). There’s probably an anatomy site or two out there with pictures a million times clearer than my attempts at description. ---
**Author:** ![Green\_Bean](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/green_bean/32/1760_2.png) [@Green\_Bean](https://boards.straightdope.com/u/Green_Bean)\ **Post date:** [April 6, 2000, 3:23am UTC](https://boards.straightdope.com/t/ass-bone/9877/5 "2000-04-06T03:23:00Z")
I think I know what you mean by “the really pointy ones,” inertia. Cyclists (and probably others too) call them the “sit bones.” That is not a technical term, of course. ---
**Author:** ![LabRat](https://avatars.discourse-cdn.com/v4/letter/l/898d66/32.png) [@LabRat](https://boards.straightdope.com/u/LabRat)\ **Post date:** [April 6, 2000, 3:48am UTC](https://boards.straightdope.com/t/ass-bone/9877/6 "2000-04-06T03:48:00Z")
The coccyx isn’t a weight bearing bone. If you sat on it, it’d hurt like hell. There are two bones that you sit on when you’re in a chair. They’re called the left and right ischium. You’ve also got a left and right illium (put your hands on your hips and you’re grabbing 'em). You’ve also got a left and right pubis which runs from one side to the other underneath your pubic hair. Technically, the sacrum and coccyx are not part of your pelvis. They’re spinal bones. Hope this helps. * * * ---
**Author:** ![LabRat](https://avatars.discourse-cdn.com/v4/letter/l/898d66/32.png) [@LabRat](https://boards.straightdope.com/u/LabRat)\ **Post date:** [April 6, 2000, 3:51am UTC](https://boards.straightdope.com/t/ass-bone/9877/7 "2000-04-06T03:51:00Z")
Oh, if you REALLY want to get technical, you’re sitting on your ischial tuberosity. A tuberosity is a large rounded prominence on a bone. ---
**Author:** ![Green\_Bean](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/green_bean/32/1760_2.png) [@Green\_Bean](https://boards.straightdope.com/u/Green_Bean)\ **Post date:** [April 6, 2000, 4:02am UTC](https://boards.straightdope.com/t/ass-bone/9877/8 "2000-04-06T04:02:00Z")
Tuberosity sounds like a mutant potato. ---
**Author:** ![cornflakes](https://avatars.discourse-cdn.com/v4/letter/c/9d8465/32.png) [@cornflakes](https://boards.straightdope.com/u/cornflakes)\ **Post date:** [April 6, 2000, 3:05pm UTC](https://boards.straightdope.com/t/ass-bone/9877/9 "2000-04-06T15:05:00Z")
A link for every occasion! [http://innerbody.com/image/skelfov.html](http://innerbody.com/image/skelfov.html) Put your mouse over the image, and the names of the bones and ligaments pop up. ---
**Author:** ![handy](https://avatars.discourse-cdn.com/v4/letter/h/b5a626/32.png) [@handy](https://boards.straightdope.com/u/handy)\ **Post date:** [April 6, 2000, 3:52pm UTC](https://boards.straightdope.com/t/ass-bone/9877/10 "2000-04-06T15:52:00Z")
I like to think of it as a primitive tail bone. As if we once actually had a tail. ---
**Author:** ![Jinx](https://avatars.discourse-cdn.com/v4/letter/j/c6cbf5/32.png) [@Jinx](https://boards.straightdope.com/u/Jinx)\ **Post date:** [April 6, 2000, 4:10pm UTC](https://boards.straightdope.com/t/ass-bone/9877/11 "2000-04-06T16:10:00Z")
Well, you know most have touched on describing the “tail bone”, but where the pelvis and femur join help support your “cheeks”! (Ooh, my sacroilliac!) * * * “They’re coming to take me away ha-ha, ho-ho, hee-hee, to the funny farm where life is beautiful all the time… :)” - Napoleon IV ---
**Author:** ![JoeyBlades](https://avatars.discourse-cdn.com/v4/letter/j/a87d85/32.png) [@JoeyBlades](https://boards.straightdope.com/u/JoeyBlades)\ **Post date:** [April 7, 2000, 5:07am UTC](https://boards.straightdope.com/t/ass-bone/9877/12 "2000-04-07T05:07:00Z")
Ass bone? I’ve never heard it called that, except by red necks, maybe… I’ve always known of it as the tail bone, which is what my doctor refer to it as when I broght mine in broken… Let me tell you, you don’t want to break your tail bone. I broke mine about 4 years ago and haven’t been able to sit comfortably since. It’s not the kind of thing you can put a cast on, but my doctor joked, “I’m gonna have to put yer ass in a sling.” ---
**Author:** ![bibliophage](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bibliophage/32/7615_2.png) [@bibliophage](https://boards.straightdope.com/u/bibliophage)\ **Post date:** [April 7, 2000, 4:20pm UTC](https://boards.straightdope.com/t/ass-bone/9877/13 "2000-04-07T16:20:00Z")
> [@](#): > > Originally posted by KarlGauss: > **The bone just above your asshole is the coccyx. Above that, the sacrum. On either side, but higher than the coccyx, are the ischium and the ilium.** By the way, coccyx is pronouned “cock sicks”, not “cock kicks.” ---
**Author:** ![KarlGauss](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/karlgauss/32/3713_2.png) [@KarlGauss](https://boards.straightdope.com/u/KarlGauss)\ **Post date:** [April 7, 2000, 4:28pm UTC](https://boards.straightdope.com/t/ass-bone/9877/14 "2000-04-07T16:28:00Z")
That’s what I said - cock sicks.