Trenchards mixed entries - μέμφομαι and μωμάομαι

[Stephen Hughes]

Let me prefix my question by saying, in his list of words related to μέμφομαι, on page 69 of the 1992 edition, the three types of words that Trenchard lists together are present.

That is to say that within the definition of "cognates", three types of words are lumped together；

1. various parts of speech - where words have basically the same meaning, but one is a noun, another is a verb, adjective, adverb, etc.
2. derivational morphology - words have a different meanings from one another due to the addition of elements such as prefixed elements, including vowel gradation, and
3. (etymological) cognates - words which at some some point in the language were related to one another, but may not be recognisably related now.

In the entry in question:

1. μέμφομαι; ἄμεμπτος, ἀμέμπτως, and ἀμώμητος, ἄμωμος are simply the same word being used in different parts of speech - adjective vs. adverb, and one type of adjective vs. another. Also μέμφομαι, μομφή, and μωμάομαι, μῶμος, are the noun and verb of words of the same or very similar meaning,
2. μῶμος and ἄμωμος differ in meaning by the addition of an element, here the alpha-privative, μεμψίμοιρος is a combination of an unrelated word, and
3. then there is my question ...

What is the etymological relationship between (μέμφομαι, μομφή, ἄμεμπτος, μεμψίμοιρος, ἀμέμπτως) and (μωμάομαι, μῶμος, ἀμώμητος, ἄμωμος)? The words used in the New Testament are not the only words in (what Trench calls) the cognate group - others can be found in LSJ; -μωμ-, -μεμφ- -μομφ- to fill in the logical cognate-family gaps in the New Testament extant usages.

[Stephen Carlson]

According to the etymology of Beekes 2010, μέμφομαι comes from a PIE root *me-mbh-, meaning reproach, while μῶμος (whose denominative verb is μωμάομαι) remains isolated with no known etymology.

The phonological similarity between these two terms is only apparent: the initial μεμφ- comes from reduplication of a root beginning with μεφ, while μωμ- is part of the root itself. There is no way to account for the difference in vowels if they were related.

[Stephen Hughes]

So, the best thing to do is to pencil in another cognate-group heading for μῶμος, containing the four words μωμάομαι, μῶμος, ἀμώμητος, ἄμωμος, and leave the other five words (μέμφομαι, μομφή, ἄμεμπτος, μεμψίμοιρος, ἀμέμπτως) under μέμφομαι.

This does create an issue with the process of adding up Trenchard's cognate groups, to get cognate group totals and the derived cognate group based vocabulary-learning efficiency rankings.