Wetback is a derogatory term used in the United States to refer to foreign nationals residing in the U.S., most commonly Mexicans.
[4] It was used officially by the US government, including Dwight D. Eisenhower in 1954,[5] with "Operation Wetback", a project that involved the mass deportation of illegal Mexican immigrants.
The earliest known recorded use in this way is by John Steinbeck in the novel Sweet Thursday, the sequel to Cannery Row, with the sentence "How did he get in the wet-back business?"
It was originally used as a verb in 1978 in Thomas Sanchez's Hollywoodland, with the meaning "to gain illegal entry into the United States by swimming the Rio Grande".
[8] The equivalent Spanish-language term used in Mexico, Central America, and by Latinos in the United States is espalda mojada, and is often shortened to mojado.