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.
Word used to express general approval or awesomeness of something. Drop emerged in its slang form in London in late 2013 and early 2014. Synonyms include dope, sick, hench, fly, swag, gnarl and rad.