pandillero
/pandiˈʝeɾo/ · B2 · noun · m
gangster
🔫👥 pandillero = pandilla (gang) + -ero (person of) → person of the gang
Pandilla means gang or group of friends, and the suffix -ero marks a person tied to something, like in zapatero or panadero. So a pandillero is simply someone who belongs to a pandilla.