В словаре суттта-централ как-то не очень понятно:
Aṭṭhamaka
= aṭṭhama the eighth.
1. lit. Mil.291 (att˚ self-eighth).
2. as tt. the eighth of eight persons who strive after the highest perfection, reckoned from the first or Arahant. Hence the eighth is he who stands on the lowest step of the Path and is called a sotāpanna (q.v. Kv.243–Kv.251 (cp. Kvu trsl. 146 sq.); Ne.19, Ne.49, Ne.50; Pts.ii.193 (+ sotāpanna).

У меня в перечне (санскритском, никайском, из восьми категорий) так: sraddhanusarin, dharmanusarin, astamaka, srota-apanna ....