"Bob (this one)" wrote

No, seriously...

Pastorio

I wish you had been. It is an interesting subject with no definitive answer
that I know of. The use of "biscuit" in non-American terms is pretty
uniform. American biscuits are, in some ways similar to scones, but lighter.
I suspect two possibilities but have no reason to except "gut feeling" which
is notoriously misleading.

Having had an Irish mother, I have had some very light scones and light
breads that could almost be called biscuits.

Also, I see a lot of similarities between American biscuits and certain
dumplings. Both in taste and texture.

Many of American food names, including cookies, came from the Dutch. Perhaps
there is a convoluted name twist here. Or perhaps, the Irish and Scottish
immigrants in the south simply 1) changed the meanings as time passes or 2)
followed some antiquated language usage which is a common thread with these
people.....many American English constructs are old styles that differ from
modern British English.

I think not. So let me suggest a third possibility, with your indulgence:
The name cookie (Dutch) having been well established in America, we have a
loose cannon in the term "biscuit". We have Irish scones and dumplings. We
are using a simple recipe, easy to make and quite variable as to contents.
What to call 'em?

As far as I am aware, no other cuisine makes anything identical to American
biscuits. Similar sure, identical...no. But wait! American biscuits are
eaten just like scones and also are used exactly like dumplings!

Holy Crap! It is those Netherlanders again! Oh, and along with American
contrary inventiveness too. Both helped change Irish immigrant food to a new
art form with a borrowed name.

I'm just speculating idly here, so feel free to cut my hawsers. The OED
won't be of much help here I think. An American food with a borrowed name
not in use in America. Why? Dunno really. It works though. Unlike the
American use of pants when they mean trousers.

Charlie