Definitions by Foxsong
cow
common
Used by horsemen to describe a horse that is bad-tempered or recalcitrant. Slightly more perjurative than cow, with which it is sometimes combined.
drop
Horsemen's term for a rider falling off, as in the horse "dropping" the rider. It does not imply that the horse intentionally removed the rider, but rather that the rider fell through his own lack of skill.