"Cock-throppled" is an adjective which was originally used to describe horses whose windpipe bends outwards noticeably when they are reined. Today the term is used by extension to describe people who have bulging Adam's apples.
The term derives from the word "thropple" which means the throat or windpipe, particularly of a horse or other animal, and the word "cock" meaning "rooster," as said horses were seen to have necks resembling those of a rooster.
Some examples of actual usage, courtesy of the OED and Google:
- The throppell..should when the horse reyneth be straight and even, not bending like a bowe which is called cock-throppled, and is the greatest signe of an ill winde. (1617)
- [The Horse] was not..neck-reversed, or cock-thrappled, ewe-necked or deer-necked. (1843).
- ...bestrode a large, raw-boned, cock-throppled nag named "Nelson" (1897)
- ...the self-proclaimed beauty and brilliant political analyst Ann Coulter, the woman for whom "cock-throppled" was undoubtedly coined. (2006)