A horse that has one parent that is wild or some people say A domesticated horse that has become wild again
This can mean that the horse will let you pet or brush it but may not let you ride it.
This would depend on how the term was used. If you mean ' the horse threw a shoe.' that would mean the horse lost it's shoe somehow. If it was ' the horse threw the rider.' it means the horse lost it's rider somehow. It can also mean the horse 'threw' a foal ( gave birth/sired a foal). There are many meanings to this term, depending on how it was used.
To be a horses @$$, is to be an @$$hole
The term "horse for sale" is used in horse trading. It general means there is not a set price on the horse and the buyer should contact the seller to get more details.
A mustang is a horse too. The name comes from the term "horse-power".
stocky like a horse or dog
It means losing a horse shoe.
If you mean with abridle, just not using the reins, then there really isn't a term for that. If you mean with out a bridle, the term you are looking for is bridleless.
Pony is the term used to describe a horse under 14.2 hands high. If it is any higher, it is a horse. The term has nothing to do with age or gender.
It means to stop suddenly, not to get to the goal. To pull up is a horse riding term meaning to pull on the reins to make the horse stop.
Are you sure you do mean shank's mare which is a term for going on foot ? It is a kind of joke to say something like "we rode shank's mare" meaning we had to walk.
I've personally never heard the term 'to grass a horse'. However the term to 'putting a horse out to grass' or 'the horse is on grass' are widely used in the UK. I would assume therefore that it would be the same thing as those terms. A horse at grass means it is eating pasture grass and may or may not be supplemented with hay or hard feeds.
It means to stop suddenly, not to get to the goal. To pull up is a horse riding term meaning to pull on the reins to make the horse stop.