piquetero: piquetero (member of the Argentinian unemployed workers movement)
Hoy el wiki lo define asi: Los piqueteros son activistas, que pertenecen al movimiento social iniciado por trabajadores desocupados en la Argentina a mediados de la década del '90, poco antes de que la crisis económica provocada por la desindustrialización y reducción de las exportaciones argentinas estallara en 1998, dando lugar a un período de grave recesión que llevaría al gobierno de Fernando de la Rúa a un fin anticipado.
Nacidos como una agrupación ad hoc formada para canalizar la protesta contra los despidos de trabajadores en la empresa del Estado Yacimientos Petrolíferos Fiscales (YPF, luego absorbida en el conglomerado internacional Repsol YPF) en la provincia argentina de Neuquén, los cortes de ruta ("piquetes") realizados como medio de protesta dieron su nombre a los numerosos movimientos de desempleados que se han institucionalizado progresivamente, formando la contrapartida obrera a los cacerolazos empleados por la clase media-alta para expresar su descontento con la acción gubernamental.
Y el wiki en ingles dice:A piquetero is a member of a political faction whose primary modus operandi is based in the piquete. The piquete is an action by which a group of people blocks a road or street with the purpose of demonstrating and calling attention over a particular issue or demand. The trend was initiated in Argentina in the mid-1990's, during the Administration of President Carlos Menem, soon becoming a frequent form of protest in other parts of the country. Seventy percent of the piqueteros are women [1].
The word piquetero is a neologism in the Spanish of Argentina. It comes from piquete (in English, "picket"), that is, a standing blockade and/or demonstration of protest in a significant spot.
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As I've argued before, it can be useful and interesting to compare the two versions of wikipedia. I actually think that picket is a false cognate here in English. Most pickets in North America do not block streets, which is the whole point of a piquete. I would use barricade or road block. I do agree that it's worth importing piquetero into English as a neologism, but I do think that for most audiences the first time you use it you need to describe it, as above.
Ojo que a piquete in Argentina is not only or necessarily done by piqueteros, but can be done by students, etc. To make things more confusing, as I understand it piqueteros also do marches and other forms of protest that aren't always just road blocks.