Background:
I was looking at 1Tim. 5:2 and wanted to investigate ἁγνεία and it's roots. In the course of that study I clicked the root and noticed that Logos considers the root of ἁγνεία to be αγιος (sic). Trying "search this resource" proved to cover too wide a field of meaning to be helpful, so I opened (among other things) the Exegetical Dictionary of the New Testament which has the following grouping (TDNT also groups ἁγνεία under ἁγνός not ἅγιος):
ἁγνός, 3 hagnos pure, undefiled, chaste
ἁγνεία, ας, ἡ hagneia purity, chastity
ἁγνίζω hagnizō purify, sanctify
ἁγνισμός, ου, ὁ hagnismos purification, sanctification
ἁγνότης, ητος, ἡ hagnotēs purity, sincerity
ἁγνῶς hagnōs purely, sincerely
This made me wonder whether Logos has it right. Certainly ἅγιος and ἁγνεία have very similar spellings and meanings that seem to overlap, but is that enough to conclude that ἅγιος is the root of ἁγνεία?
Question:
How would one determine whether Logos has it right regarding the root ἁγνεία? Would it not be better to suggest ἁγνός as its root?
Shouldn't Logos be following the apparently accepted scholarship of both
TDNT and EDNT here? If not, what can you tell me about accepted
scholarship regarding the root of ἁγνεία?