Well, that’s a horse of another colour. 
While I have no cite, I believe “stallion” is not used by the racing crowd due to perceived negatives of the term (a high strung, dangerous animal).
As mangetout proposes, it’s a case of usage varying with the sphere of interest.
In horse racing stallions do not race. The appellation is reserved for male horses kept for breeding purposes. However if a stallion fails at stud it may return to the track, in which case it becomes a horse again, unless it is under five years old, in which case it goes back to being a colt.
The term ‘mare’ is used in both racing and breeding to describe a female horse over the age of four. Of course, when a breeding mare foals she becomes a dam to the foal while remaining a mare in every other sense.
Geldings aren’t much interested in breeding.
There’s a hierarchy in language that might help in threads like this.
Grammar hardly ever changes. Violate grammar and you’re almost certainly wrong.
Spelling is iffy. Some spelling mistakes become enshrined, most don’t. (Putting “apostrophe’s” in when not needed is grammar, not spelling, which is why it irritates so many people when they see it.)
Pronunciation is slippery. There is no received standard American dialect, so most words have several different and distinct variations. When it does change it changes rapidly.
Meaning is pretty much by definition guided by actual use. If people use a word in a certain way long enough, that’s what the word means. Some fight this, but it’s futile.
Lectern and podium now have the same meaning. Try spelling them lecturn and podiem, though, and see where that gets you.
You’re probably referring to Judit Polgar (one of the talented Polgar sisters).
First, ‘Chess Champion’ doesn’t mean anything in particular. If you win your school chess tournament, you can rightly call yourself ‘School Chess Champion’.
Next there are 3 international playing titles awarded by the World Chess Federation (FIDE). In ascending order of merit, they are:
- FIDE Master (FM)
- International Master (IM)
- Grandmaster (GM)
Since far less women play chess than men (shame!), FIDE decided to ‘encourage’ women by giving 2 extra titles:
- Woman International Master (WIM, roughly equivalent to FIDE Master)
- Woman Grand Master (WGM, roughly equivalent to International Master)
This meant that some people started using men’s GM to distinguish from woman GM. :rolleyes:
The correct way to say it is that Judit Polgar is a Grandmaster.
N.B. She is currently ranked 20th in the World.
A herd. 
Your final term, “horses”, comprises the four subsets that precede it.
Chez Guevara, am I correct that g is used in racing forms to indicate a gelding?
Continuing the hijack:
What I’d like to know is how the blazes you can talk about mules without discussing their parent stock, and the fact that they are not the same species as either of their parent stocks? And, if mule is that old, how old is hinny? Or is hinny a more recent word, and for a while mule was a gender neutral term, too?
(For those not aware of it, a hinny is the female analogue of a mule.)
By continuing to eat oats, primarily.
Well, the issue has been sliced, diced, and led astray into very interesting tangents. (You can lead a horse astray, but you can’t make a mare a cock.) With all that nailed down, here’s another little question:
Is this hodgepodge a “mare’s nest,” or do we go to the gender neutral “horse’s nest”?
Yes, she does.
“Fewer”. Although “less” is justifiable, given that (barring Judit Polgar) the standard is way lower. For example, Vera Menchik dominated women’s chess for years, but at the Carlsbad tournament of 1929 she finished last by a long way.
(Though I personally was once horribly beaten by a slip of a girl in a club match.)
I had to double check this. A hinny is not a female mule. Hinny and mule are both gender neutral terms. The difference is the breeding.
A hinny is the offspring of a male horse and a female donkey. A mules is the offspring of a male donkey and a female horse. Hinnies tend to be smaller, possibly as a result of the smaller animal doing the gestating.
As an aside, it looks like (Wikipedia) a female mule is called a molly and a male is called a jack. On the internet, it looks like the standard is male hinny and female hinny. If the naming convention reverts to the donkey side of the family, it would devolve to jack and jenny.
Just to be pedantic - which fite this thread so well.
Yes, that’s correct.
And now I’d like to throw a spanner in the works of my post #9. I had assumed that horse racing and breeding terminology was constant across the globe but looking at this Australian glossary of breeding terms I learn that their definition of a colt is an entire male under the age of four years (as opposed to under five in the UK) and that a filly is a female under the age of four years (as opposed to under five in the UK). This surprises me no end.
Can you in turn, ETF, confirm that the UK nomenclature applies in the US?
To hijack you hijack. Skene, not scene. Skene (ski-nii) is kind of the equivalent on the stage house in Elizabethan theatre. It’s a permanent back drop with entrances and exits which was also used as a storage and dressing space, again, like Elizabethan stage houses or Spanish Golden Age tiring houses.
That should be “your hijack” and I forgot to click the quote button in the quick reply, but I was responding to this
Very cool, thanks. For some reason I’d been operating under the impression that a mule was always male and hinny was always female. Since both occur via breeding across species lines, I figured it was just something hinky in the biology that made it impossible to have a female mule, or a male hinny.
Which now that I look at that assumption again, is really silly. :smack:
I think I know why it differs in Australia, and possibly other southern hemisphere countries also, but to explain it here would be a blatant hijack. 
I’ve been involved with horses most of my life. I’ve participated in and attended horse shows, team penning events, rodeos, auctions, cutting horse competitions, and more. I know many dozens of ranchers and horse breeders. Until today, I’ve never heard of the generic species name “horse” being used as a gender-specific substitute for “stallion.”
The The National Thoroughbred Racing Association (the governing body of U.S. thoroughbred horse racing) has selected at least one mare (Azeri in 2002) as “Horse” of the Year in the last decade, and currently has at least one mare (Ginger Punch at #7) in its listing of “Top Ten Horses.” It appears they aren’t going to great lengths to push a gender-specific definition either.
I have a gelding and a mare, and I intend to continue telling people who ask that I have two horses.
No, it doesn’t. Read what I was replying to.
I did read it. I’m still correct. Fillies, colts, mares and stallions are all horses. A horse is either a colt, filly, mare, stallion, or gelding. Thus the collective word is “horses” and in a group they are a “herd”.
And a mixed group of brigs, brigantines, destroyers, aircraft carriers, etc. would be collectively referred to as “ships” or a “fleet” because that is the generic name for them, even though when speaking of an individual ship one would more correctly use the particular appellation for it.
Herd of horses, fleet of ships.