By mostrenco, within the civil and administrative law, it is understood the goods - called real goods - that have no known owner. This can happen both because of never having had an owner, or because the owner has left in obvious abandonment to the good, or still the last owner is not there, or has died without establishing his destiny.
However, according to the dictionary of the RAE, the term mostrenco has another completely different meaning colloquially; it is used as a synonym of: ignorant; clumsy; stupid; rude.
In the glossary of gaucho and creole terms in Argentina, a foreign animal is defined by "mostrenco."
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