Like malandragem, in Brazil it's not a term of endearment. But in our roda-centered world, the word has become an archetype of an older, more relaxed style of going about the business of capoeira. It comes from a time (pre-1940s) when there was no such thing as a capoeira school. The art was learned only on the street, hand-to-mouth. Generally, before academies of ginga existed, a young man (and it was usually a man) interested in learning how to artfully kick and dodge had to hang around street rodas, soliciting advice from the players there. Eventually, if the stars aligned and some persistence was applied, one mestre might take the young man aside and offer genuine guidance. An arrangement was established, a partnership was entered. They might meet together to train as a pair or with a few friends, attending rodas periodically.
But, looking back, we wouldn't necessarily call it formal instruction — that is, the student's "lessons" didn't follow any standard curriculum with regular intervals to mark his progress. For the most part, the roda was the classroom and the student's knowledge came by snatching insights on the fly, tempered by his master's advice on technique and strategy. Vadiar and vadiação symbolize this earlier, more anarchic capoeira. It is not merely a way of doing capoeira, but also learning how to be a capoeirista.
In a very true sense, the way the vagabond occupied the roda mirrored the way he occupied the world. Historically, the majority of capoeiras were saddled with deep poverty. They were forced to take a pragmatic approach to procuring food, shelter, and money. It's a universal truth that the lower class have difficulty making their voices heard or their needs met. The law (what we—21 st -century Americans—might term the "formal rulebook for living in a society") offers little help to severely poor, severely impoverished peoples. Self-sufficiency is more important for survival than law-abiding- ness. So, much like the malandro, the vagabond lives mainly by his wits. Lacking the fallback cushions of money or status or reputation, the vagabond's existence falls on the slender line between poverty and starvation. In the face of such a life, the twin structures of law and social norms become a little flimsier, a little more open to interpretation. Necessity is a harsher master than a policeman could ever be.