also slow poke, 1848, American English from slow (adj.) + poke (n.3), the name of a device, like a yoke with a pole, attached to domestic animals such as pigs and sheep to keep them from escaping enclosures. Bartlett (1859) calls it "a woman's word."
in England they call a slowpoke a slowcoach
slovenly
slow
slowdown
slowly
slowness
slowpoke
slubberdegullion
sludge
sluff
slug
slug-a-bed