I'd guess that 'algebraic' refers to the emphasis on composability: you create new procedures by composing existing procedures (forming a free monoid), as oppos

I'd guess that 'algebraic' refers to the emphasis on composability: you create new procedures by composing existing procedures (forming a free monoid), as opposed to creating procedures via a 'telescoping' structure of encapsulation. Perhaps it is further meant to imply associativity in some sense.