"to drug a man unconscious and ship him as a sailor," 1854, American English, from the practice of kidnapping to fill the crews of ships making extended voyages, such as to the Chinese seaport of Shanghai.
Shanghai
Chinese seaport, literally "by the sea," from Shang "on, above" + hai "sea." In 19c., a long-legged breed of hens, supposed to have come from there; hence U.S. slang senses relating to long, tall persons or things.
The men were shanghaied after being drugged
shan't
shanachie
shandy
Shane
shanghai
Shangri La
shank
Shannon
shantung
shanty