That is to say that within the definition of "cognates", three types of words are lumped together；
- various parts of speech - where words have basically the same meaning, but one is a noun, another is a verb, adjective, adverb, etc.
- derivational morphology - words have a different meanings from one another due to the addition of elements such as prefixed elements, including vowel gradation, and
- (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:
- 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,
- 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
- then there is my question ...