derogatory for "Vietnamese," 1969, U.S. military slang, of uncertain origin.
"supreme military commander," 1620s, from Italian generalissimo, superlative of generale, from a sense development similar to French general (see general (n.)). Parson Weems applied it to George Washington. In 20c. use sometimes from Spanish generalísimo in reference to the military dictator Franco.
1917, abbreviation of military police, which is recorded from 1827. By 1809 as an abbreviation of Member of Parliament.