Waghalter: one likely to be hanged (obs.) As in they will wag (like a dogs tail) from a halter (noose). Kinda' grisly, eh?
Actually, the term "Wag"--which is still occasionally used to describe a prankster--is derived from waghalter. Extra grisly.
And on a cultural note: Ignatz Waghalter was a classical composer of the early-mid 20th century. He did not, as far as Wikipedia indicates, meet his end at the gallows. Though, being a Jew working in Berlin during the 1930s, he was forced to flee the country; he lived out his last years in NYC.