Nonsense or empty talk. Derived from the word for empty, it refers to a conversation or statement that is superficial, vain, and lacks any real substance (in the Dominican Republic, it is synonymous with pluma de burro, a phrase used to describe something trivial or nonsensical).
To speak the Basque language. In Dominican slang, the term refers to speaking in a way that is completely unintelligible or sounds like gibberish (the Basque language is a language isolate unrelated to Spanish, making it sound like nonsense to a local listener).
When people in the Dominican Republic heard two people talking in that language and could not understand a word, they said those two are speaking Basque, which in local Spanish evolved into: those two are talking vacuencia.
Derived from the word for empty (vacio), this term refers to trivial, superficial, or baseless talk. It describes speech that lacks substance or meaning, similar to talking nonsense or hot air.