Che is a word used commonly in Argentina, Uruguay, Paraguay, Valencia in Spain, and some parts of Bolivia, with usages similar but not identical to mate or pal in English. In Argentina, it is generally used like "hey" or "eh" is used in the United States and Canada.
The origin of this word is unclear. It is said that it may be derived from the native South American Guarani language's che, which means simply "I" or "my". In Tehuelche and Pampa languages che means "man" and in Mapuche language it means "people". Others, however, argue that the word che is derived from the archaic Spanish word ce, used to call someone's attention, with che used commonly in Valencia, Spain.
In other Latin American countries, the term Che is used to refer to someone from Argentina. For example, Ernesto "Che" Guevara earned his nickname from his frequent use of this expression, which, particularly to his Cuban comrades, was a curious feature of his idiolect. Guevara is popularly known simply as el (the) Che in Latin American countries. This sort of appellation based on utterance is common when persons from different cultures interact (see, for example, les goddams).
Tens of tangos names, such as Che, bandoneón or Che, papusa, oí start with the word che.
Also, Cheee! was a catchphrase used by the late José Marrone, impersonating the clown Pepitito.
Further reading
See also: Lunfardo