There are some "definitions" of aerobatics or at least "clarifications" in the document at:
https://www.caa.co.uk/docs/2628/2013...2007SERA02.pdf
there are also some mentions in the document at:
https://www.caa.co.uk/docs/620/20100...mentsCRDb2.pdf
However there are no specifically quoted pitch or bank angles for aerobatic manoeuvres though in the first document specific aerobatic manoeuvres are quoted.
I did not see any definitions at
Aerobatics either!