What does B in ABA stand for?

I'm curious to know, in the context of cryptocurrency or finance, what exactly does the "B" stand for in the term "ABA"? Is it an acronym that relates to a specific process, organization, or technology within the industry? Or perhaps it's a reference to a particular strategy or methodology? Could you please elaborate on the significance of this "B" in the context of ABA, and how it relates to the broader cryptocurrency and finance landscape?