Frentero, ra: person who says things bluntly and straight, even if his words can hurt susceptibilities.
Frentero, ra: person which is not reserved, which makes the things in front, especially when it's something improper.
There are a few meanings of FRENTERO in Colombia: Adj. m. person who says what he feels and thinks with his interlocutors. Without fear. Shed. Reckless.