Wetback (slur)
（重定向自Wet back）
Wetback is a derogatory term used in the United States to refer to foreign citizens living in the U.S., most commonly those from Mexico, especially to those residing illegally in the U.S.
Generally used as an ethnic slur, the term was originally coined and applied only to Mexicans who entered the U.S. state of Texas from Mexico by crossing the Rio Grande, which forms the border between Texas and Mexico, presumably by swimming or wading across the river and getting wet in the process.