You're going to get lots of different answers on this one. Personally, I think the name is given to the entire package. Color and pattern. That's the way it's always been, but I'm being told folks are trying to split that up.
They say the patriarchs of this line were very red. Since I've never seen one that was the color of blood, I presume they were 'redder' than most corns. I think the name was more of a goal than a description.
Until recently, all bloodreds had many traits in common.
1) They have a non traditionally patterned belly that lacked all black.
2) Their mature coloration had little or no black anywhere.
3) Their mature markings "blended" with their ground colors so as to almost make them patternless.
4) Most were redder than most corns.
5) Also almost all the first ones I saw many years ago had linear dark stripes. Not unlike a striped corn, but not very dark. I still have a few with those stripes, but you don't see that much any more.
I think the target bloodred corn is one that has:
1) Little or no black as adults.
2) Almost no obvious markings as adults.
3) Non traditional belly markings. Usually red OR white OR red and white. Black specks allowed, but not black checkers.
As you say, today we see orange, red, brown in the so-called 'normal' coloration and of course combinations with recessive colors like charcoal, amelanistic, caramel, anerythristic and complexes thereof. Of course, we're mixing them with the popular patterns too.
Your question is prudent since the name they were given denotes a color. A color of which is probably the least common. That of blood. To me, your best standard is the belly markings or lack of them. Since many can have dorsal and lateral patterns like any other corn, the belly markings will "indicate" whether it's a bloodred or not. As it is with most things, there are some bloodreds that can even fool us with their belly markings. I have and know of others with pure bloodreds with a little black on the bellies, but not the traditional checkers. If one has more than small black flecks, I'd say it's probably not a bloodred.
Don
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