Green’s Dictionary of Slang

hock n.2

[Du. hok, hutch, hovel, prison; but note gambling jargon, see Asbury, Sucker’s Progress (1938) 15–16: ‘In hock—The last card in the box was said to be in hock. Originally it was known as the hockelty card, and in the early days of Faro, when it counted for the bank, a player who had bet on it was said to have been caught in hock. Also, a gambler who had been trimmed by another sharper was said to be in hock to his conqueror; and as late as the middle 1880’s, in the underworld, a man was in hock when he was in jail. The phrase is now principally used in reference to pawnshop pledges, but it seems to have acquired that meaning in recent years.’]

[late 19C+] the state of being pawned; usu. in phr. in hock

In compounds

hock sheet (n.)

[1990s+] (US police) a list of stolen goods that may have been pawned.

hock shop (n.) (also hockshop)

1. [late 19C+] a pawnbroker’s shop.

2. [1950s] a prison.

In phrases

caught in hock

[mid-19C] caught in the act.

hock off (v.)

[2000s] (N.Z.) to get rid of, to dump.

in hock

1. [mid-19C–1950s] in prison; thus the reverse, out of hock.

2. [late 19C+] indebted to, owing both money and metaphorical debts; thus the reverse, out of hock.

3. [late 19C+] in pawn; thus the reverse, out of hock.

4. [1920s] in trouble.

on the hocks

[1930s] (US tramp) impoverished.

on hock

[2000s] on credit.