Generally, I prefer the translation of "ariyasāvaka" as "noble disciple" (thus referring to at least a stream-enterer). For example, I think the following quote from SN 48.10 aptly refers to a stream-enterer; given "vossaggā" is the quality of the factors of enlightenment described in MN 118 :
And what is the faculty of immersion?
Katamañca, bhikkhave, samādhindriyaṃ?
It’s when a noble disciple, relying on letting go, gains immersion, gains unification of mind.
Idha, bhikkhave, ariyasāvako vossaggārammaṇaṃ karitvā labhati samādhiṃ, labhati cittassa ekaggataṃ.
https://suttacentral.net/sn48.10/en/sujato
It’s when a mendicant develops the awakening factors of mindfulness, investigation of principles, energy, rapture, tranquility, immersion, and equanimity, which rely on seclusion, fading away, and cessation, and ripen as letting go.
Idha, bhikkhave, bhikkhu satisambojjhaṅgaṃ bhāveti vivekanissitaṃ virāganissitaṃ nirodhanissitaṃ vossaggapariṇāmiṃ.
https://suttacentral.net/mn118/en/sujato
However, DN 31, which appears to be a teaching to a non-Buddhist householder, contains the following:
The above, from DN 31, plus the entire sutta of DN 31, does not sound like at least stream-entry to me. DN 31 merely sounds like a teaching for ordinary moral householders.Householder’s son, a noble disciple gives up four corrupt deeds, doesn’t do bad deeds on four grounds, and avoids six drains on wealth. When they’ve left these fourteen bad things behind they have the six quarters covered.
Yato kho, gahapatiputta, ariyasāvakassa cattāro kammakilesā pahīnā honti, catūhi ca ṭhānehi pāpakammaṃ na karoti, cha ca bhogānaṃ apāyamukhāni na sevati, so evaṃ cuddasa pāpakāpagato chaddisāpaṭicchādī
They’re practicing to win in both worlds, and they succeed in this world and the next.
ubholokavijayāya paṭipanno hoti. Tassa ayañceva loko āraddho hoti paro ca loko.
When their body breaks up, after death, they’re reborn in a good place, a heavenly realm.
So kāyassa bhedā paraṃ maraṇā sugatiṃ saggaṃ lokaṃ upapajjati.
https://suttacentral.net/dn31/en/sujato
Please kindly offer any linguistic or other scholarly insights. Thank you