Dear Vinicius,
Boa is not actually an acronym, it is a name meant to be written like Boa.
In May 2012, when the work on Boa project began, the project was initially called `ULCA' that stood for Ultra Large Scale Code Analysis. Now, we immediately realized that ULCA wasn't a very catchy name.
So, after some thinking I suggested to my wonderful collaborators Drs. Robert Dyer, Hoan Nguyen, and Tien Nguyen that we go with Boa, after the constrictor snake Boa (https://en.wikipedia.org/wiki/Boa_constrictor). My collaborators were very kind to go along with it, and so the name stuck. Later on we named the framework that allows Boa code to run locally Candoia (see: http://design.cs.iastate.edu/papers/MSR-17/, and http://candoia.github.io), a subspecies of Boa (https://en.wikipedia.org/wiki/Candoia_bibroni).