-ής, -ές is a suffix used to form adjectives. The entry on -ής, -ές in Smyth’s Grammar §858, reads (Herbert Weir Smyth, A Greek Grammar for Colleges):
5. ες (nom. –ής, –ές): primitive: ψευδ-ής false (ψεύδ-ω deceive), σαφ-ής clear, πρην-ής prone, ὑγι-ής healthy. Very common in compounds, as ἀ-σφαλ-ής unharmed, secure (ἀ-priv. + σφαλ- in σφάλλω trip).
So the compound adjective εὐ-γεν-ής ‘good + breed’-ής for ‘noble’ is analogous to ἁ-σφαλ-ής ‘un-tripping’-ής for ‘secureʼ.
Γένεσις /ɡénesis/ “Genesis, origin” consists of the verb root gen- “to originate”, and the ending -esis.
The -εσις ending of Greek genesis has two components. The –sis component is a nominalisation, indicating the result of a verb. Cf. ly-sis ‘solution’ < lyō ‘solve’; gennē-sis ‘birth’ < gennaō ‘give birth’; pep-sis ‘digestion’ < peptō ‘digest’; theōsis ‘becoming God’ < theoō ‘make a God’.
The vowel before the –sis, if any, depends on the conjugation of the verb.
And here I get stuck, I’m afraid. I can’t work out why the vowel in genesis is an epsilon instead of a zero, *gen-sis > *gessis, or an a which corresponded to the Indo-European schwa, cf. teinō ‘stretch’ > tn-sis > ta-sis ‘tension’. I think somehow this is a pattern with second aorists, e-gen-omēn ‘I became’ > gene-sis ~ e-sch-omēn ‘I was had’ > sche-sis ‘relation’.
But in any case: the vowel is not part of the suffix, but a connector.
EDIT: the actual answer is Neeraj Mathur’s answer to The Greek word genesis (γένεσις) has the root gen, but where does the suffix -esis come from? I’m leaving this up because it takes you halfway there, and Neeraj resolves the -e- issue where I got stuck; and this is good information to know for less archaic verbs anyway.
I’ve just written an answer about Pāṇini. I know what a macron is, and I know what a retroflex nasal is. I also know that the Sanskrit grammarian is not to be confused with an Italian sandwich.
Nevertheless, in my answer I referred to him as Panini. And I do not feel guilty for doing so.
Diacritics for other languages are appropriate in scholarly writing, and when you are writing for a bilingual audience, which will wince to see them missing. In a more casual context, on the other hand, it does come across in English as pretentious.
There is also a long standing convention that we are not as fastidious about diacritics on proper names. Proper names are embedded in otherwise purely English text. There is a strong driver to nativise them orthographically, since they are effectively used as part of English. The same goes for loan words. I pronounce jalapeno with a velar fricative and palatal nasal, because I’m pretentious like that, but I would still hesitate to use a tilde.
Language is full of contradictory pressures, and this is yet another instance: assimilation versus fidelity, nativisation vs exoticisation. The pendulum swings, as a matter of fashion, but the drivers behind each are legitimate. Dropping the tilde in a loanword is not disrespect to Spanish: it demonstrates how thorough the influence of Spanish has been in English, to have produced a nativised loanword.
I wasn’t familiar with this user. All I can tell from searching is, he’s deleted his account in the last few months.
In the case you raise of count, this is simply Assimilation (phonology). It’s not that the m and the n are interchangeable, it’s that nt is easier to pronounce that mt, because both the n and the t are alveolar, so you do not have to move your tongue and lips between the two sounds; m and t on the other hand have different places of articulation.
A lot of sound change involves assimilation, since a lot of sound change is driven by ease of pronunciation; e.g. computare > compter > conter > count. The reverse change, Dissimilation, is rarer, and usually involves removing repetition of the identical sound, rather than making two different sounds less similar.
So let me tell you an anecdote.
I have a relative in Greece of roughly my age, who was studying at university away from home, 20-odd years ago. (Since “home” is a town of 7000 people with only a nursing school, that’s not hard to imagine.)
Said relative at some stage took a job distributing junk mail. Not an uncommon thing, you’d think, for a uni student wanting to earn a bit of pocket money.
Said relative kept their part time job secret from their parents, and begged me not to tell.
It would have been humiliating to them, if it had got out: it would have implied that they were incapable of supporting their child.
It is, as John Carrick says, a cultural thing. There are different notions between Greek and “Western” society on how important the family is vs the individual, how important it is for an individual to be independent vs interdependent, and how important the family’s face is.
Because Greek didn’t have an ŋ letter, although they knew that the sound existed.
Phonetically, the final -n in prefixes was often assimilated phonetically to the following letter:
Now if you put syn- in front of a velar, and the -n- undergoes assimilation to a velar just as it did to a bilabial or a liquid, then you would expect the n to go to an ŋ:
Those forms show up in Greek alright, but they’re written with a gamma where you’d expect the ŋ: <sygkopē>, <syggrapheus>, <sygkhysis>.
But we do have evidence that the gamma in that position stood for an ŋ after all.
ut Ion scribit, quinta uicesima est littera, quam uocant agma, cuius forma nulla est et uox communis est Graecis et Latinis, ut his uerbis: aggulus, aggens, agguilla, iggerunt. in eius modi Graeci et Accius noster bina G scribunt, alii N et G, quod in hoc ueritatem uidere facile non est. similiter agceps, agcora.
As Ion writes, there is a 25th letter, which is called ‘agma’, which has no shape, but a phonetic value that is the same in Greek and Latin, as in the following words: aggulus, aggens, agguilla, iggerunt. In words of this type, the Greeks and our Accius write a geminate GG, while others write NG, because it is difficult to recognize the real sound in the former; similarly agceps, agcora.
jIDel’eghmeH jIbomchugh, chay’ vIta’?
ghopwIj roSHa’moH qaD, ’ej jatwIj qa’.
.i mi te pemci mi .ei ta’i ma
.i go’i lesedu’u mi mo da
Kiel poemi pri mi mem? Ĉu praa
la stilo estu? Aŭ ĉu forbalaa?
De memet si canendum, fulmina
extinguant niteantque carmina.
Περὶ ἐμοῦ εἰ γέγραφ’ ἀγαθά,
ψευδῶς· ψευδῶς γ’ εἰ πλεῖστα χαλεπά.
A poem on myself? It won’t scan far.
Best leave it be. Best leave things as they are.
Ποίημα λέει για τα μας; Αλλού αυτά.
Ιδού η Κβόρα· ιδού το πήδημα.
[Klingon] If I were to sing in order to describe myself, how shall I accomplish it?
The challenge paralyses my hand, and it replaces my tongue.
[Lojban] I will be the author of a poem about me, the obligation is; in what method?
I will do so about the concept that, for x, I shall be in what relation to x?
[Esperanto] How shall I poem about my own self? Should the style
be primordial? Or should it be sweeping things away?
[Latin] If it is time for songs to be sung about me myself, let songs
extinguish and ignite thunderbolts.
[Ancient Greek] If I have written about myself good things,
it’s false; and all the more false if most things are harsh.
[English] A poem on myself? It won’t scan far.
Best leave it be. Best leave things as they are.
[Modern Greek] A poem about us, he says? Pull the other one.
Here’s Quora; here’s the leap.*
*The Boasting Traveler – Fables of Aesop:
A Traveler, on returning, boasted of the many and heroic deeds he had performed. Among those he boasted that when in Rhodes he had leaped further than anyone else found possible and that he could call upon many in Rhodes who could stand as a witness. “There is no need of witnesses,” said a bystander, “simply pretend this is Rhodes and leap for us.”
[In Archaising Modern Greek: “Here’s Rhodes, and here’s the leap.”]
See:
The factors pointed out in those answers are not unique to any one language; they are endemic to any human language.