Not a general term for the substance, i.e. feces, but for one “unit”? Is there one? It isn’t “fecal unit”, is it?
Bowel maybe?
Formerly known as Nec3f on the AOL SDMB
[ul][li]For rabbits (and I think deer) the term is a “pellet”.[/li][li]“Bowel movement” I think applies to the substance as well as the action. But I think it also refers to everything in a single evacuation, not the unit you’re looking for.[/li][li]“Dung heap” applies to an animal’s BM if it makes a nice pyramid shape. But it’s still not a unit measurement.[/li][li]“Cow pie” for cattle. And since theirs coalesces after evacuation, it’s a unit.[/li][li]“Road apple” is a unit, but only if it’s in the road and about the size of an apple. :)[/ul][/li]Well, it’s getting rather slangy now. Maybe if I’d gone into scatology… (I betcha there’s a field with a lot of work/shit jokes. “I don’t have to put up with this shit. Oh, wait. I guess I do.”)
“Stool”.
You can have a loose stool, formed stool (“twice around the bedpan and pointed at both ends”), watery stool, (god forbid) frothy stool, bloody stool, black stool, hard stool…
“Bowel” refers to the intestine, not the product thereof.
“Bowel movement” technically refers to the act of producing a stool.
In the ICU, when your patient tries to die, you call a “Code Blue”. When your patient begins to helplessly squirt stool in the bed so that the stool works its way into the bedrails and up the patient’s back to his neck and drips onto the floor (this happens all the time, which is why I really need a raise) you call a “Code Brown”.
That’s the last time I read the Straight Dope Message Boards before breakfast. 
Thanks for sharing that Holly. Urgh.
It only hurts when I laugh.
I know a fossolized turd is called a coprolite.
Why would you need a singular term for feces?
Oh and check out the rich tapestry of poop names:
http://www.straightdope.com/classics/a1_287b.html
Not sure I’m up to more hospital humor, but the question remains as to when ‘stool’ is a mass noun and when it’s a [I forget the term] noun with the plural ‘stools’.
Ray (not stool pitchin’)
So what’s wrong with there being a countable/discrete noun ‘fecis’?
Ray (a no 'count)
“which is why I really need a raise”
—Holly
Hey, watch it there, Holly.
We don’t want those poor administrators to go hungry, do we? 
Ain’t "managed care a wonderful thing?
Peace,
mangeorge
I think you are all being fecetious.
I think ‘stool’ refers more to the substance, rather than an actual unit (so to speak). As for fossilized poop (I will never forget the episode of 3-2-1 Contact where a scientist actually re-softened prehistoric caveman doody and gave the kids a sniff), the substance in general is coprolite, while an individual ‘stone’ is a coprolith.
Since we apparently do have a Greek term for turd, why don’t we call it a coproid?
On the same note, the Latin word for ‘thrush’ is turdus - hence the common American robin, being a member of the thrush family, bears the taxonomic name of Turdus migratorius - an apt description if I ever saw one!
Cave Diem! Carpe Canem!
A log.
Faeces is a Latin word, the singular of which is faex. Or in the American spelling, fex. So a single turd is a fex.
So, if I tell my buddies there was a “three flush fex” in my toilet, they’ll know what I’m talking about, right?
Just a little off-topic, this reminds me of one of my favorite math jokes. Draw three pines (firs, oaks, whatever) and ask a friend, “What number does this represent?”
Answer: 9 (tree + tree + tree)
Now there’s a sandstorm. After is has settled, what number have you got?
Answer: 99 (dirty tree + dirty tree + dirty tree)
Finally, a bird comes along and drops a stool/fex/whatever on each tree. What number?
Answer: 100 (dirty tree and a turd + dirty tree and a turd + dirty tree and a turd)
Holg, you crack me up.
Holly, geez, thanks for the memories…uck!
And can it be that in a world so full and busy, the loss
of one weak creature makes a void in any heart, so
wide and deep that nothing but the width and depth
of vast eternity can fill it up!
-Charles Dickens “Dombey and Son”
Me:
MrKIA:
Fantastic answer.
Holly said:
Holly, as hurl-inducing as this description was, it made me want more information. To wit: How do you deal with a “Code Brown” when the person’s injuries make it extremely dangerous to move them (e.g. a spinal injury)?
Live a Lush Life
Da Chef