Synonyms for Lockup:

n.

precinct, cop shop, police station, station house, tank. clink, Calaboose, big house, hoosegow, free, pokey, can, slammer, house of correction, stir. •cell (noun)
keep, dungeon, cage, pen, coop, bastille.
•drunk tank (noun)
tank.
•jail (noun)
brig, reformatory, house of correction, pound, stockade, jailhouse, cell.
•lockup (noun)
cooler, prison, pokey, hoosegow, slammer, clink, locking, Calaboose, penitentiary.
•penal institution (noun)
penal colony.
•penitentiary (noun)
big house.
•pokey (noun)
pokey.
•police station (noun)
Calaboose, station house.
•prison (noun)
confine, dungeon, gaol, penal colony, oubliette, reform school, prison, pillory, irons, brig, harness, handcuff, pinion, coop, manacle, jailhouse, collar, shackle, Alcatraz, pound, reformatory, keep, jail, tether, cage, stockade, cell, fence, penitentiary, bridle, pen, bastille, San Quentin, straight jacket, cooler, vise, jug, stronghold.

Other synonyms:

hoosegow, slammer, cop shop, Calaboose, big house, house of correction, pokey, police station. clink. precinct. can. tank. •Other relevant words:
hoosegow, pokey, slammer, precinct, locking, Calaboose, can, stir, station house, clink, big house, house of correction, police station.

Usage examples for lockup

1. If the truth must be told, the half- breed was thankful that he had such a comfortable home for the time being, knowing it was much better than any the Indians could offer him, or better than he would get at the Gonzales lockup – For the Liberty of Texas by Edward Stratemeyer