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beaner

American  
[bee-ner] / ˈbi nər /

noun

Slang: Extremely Disparaging and Offensive.
  1. a contemptuous term used to refer to a Mexican, a Mexican American, or, less frequently, a Latino of other national origin or descent.


Etymology

Origin of beaner

First recorded in 1965–70; bean ( def. ) + -er 1 ( def. ) (from beans being regarded as a staple in Mexican diets)