It is a polysemic word that can be substantive meaning to cover paper or other material to introduce money, documents, cards, letters, etc, with different shapes, colors and sizes. It can also be a preposition with many circumstantial semantic nuances: up from about in, before, by, in addition a prefix derived from the Latin preposition super, as overprotection, bonus, sobresdrujula, various verbal forms of the verb overload overrun. In the jargon of the cot, bed young: I'm going to rub to the envelope.
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