A man-child or an adult who still acts like an immature kid despite having the body of a man. (In the Dominican Republic, it is commonly believed the term originates from the English words man and son).
Leave him alone, the poor guy is nothing but a big mangansonaso.
A term for someone who is incredibly thick or dumber than a bag of rocks. It refers to people who are such idiots or so slow that they seem like they lack basic mental capacity (in the Dominican Republic, it usually describes a grown man who acts like a big, lazy child).
A guy who has four kids and a job as a truck driver, yet he is out in his yard playing marbles with the neighborhood kids like a total Manganson.