It means they are frightened
They can get spooked at anything, but being separated from their herd can make the horse feel vulnerable or lonely.
spooked
A common spooked horse will kick for protection and then run away!!!!!
A horse is generally spooked by snakes and doesn't like dogs.
Is when a horse or anything is frightened or scared of something
A lot of times horses are spooked by creatures such as snakes. So if a horse starts freaking out and tries to buck you off while you're riding it, it was probably spooked by a snake or something else.
Spooked
Do not use your horn directly behind a horse rider or you will spook the horse. A spooked horse can be dangerous to the rider.
I have experienced this myself so I have a say, well when the horse darts forward, maybe cause you kicked or whipped him to hard or he got spooked, there is more reasons but the one when the horse gets spooked one is the most relevant, anyway you fall off because the horse can do it so intently that you can take it by surprise and fall off because of the sudden change of speed.
Woah! You spooked me.
there is really no accurate answer but it depends on how scared it is
lollz