noun, masculine/ˈɲeɾi/plural: ñeris
idiot, fool
Popularized and used in the 2000s in Uruguay by the "planchas," a social group with rather low incomes and a certain type of clothing that set them apart from the rest. It's a way of addressing a friend (or not), like "boludo" in Argentina, "wey" in Mexico, or "pata" in Peru.