[Americanchild]

I can tell this semantics game is very important to you, so I'll concede this point

Ah shucks! What's the world coming to when Freepers won't play with me! :)

[HairOfTheDog]

OK - I'd use 'fall off' to mean the rider just didn't stay with the horse, because they jumped, lurched, tripped, turned or ran off. I'd use 'thrown' if the horse actually bucked or reared as a deliberate act to unhorse the rider.