Possibility \#9

Possibility #9

When ṃ is followed by a vowel, the vowel may be elided.

The ṃ then may change according to Possibility #2

e.g. abhinanduṃ + iti

> abhinanduṃ + (i)ti

> abhinandunti

In Kaccāyana this is called (40) paro vā saro and

(31) vagg’antaṃ vā vagge.

ṃ + vowel > elision + nasal

abhinanduṃ	iti	abhinandunti	they appreciated
ahaṃ	iti	ahanti	“I”
appaṃ	api	appampi	even a little
ayaṃ	api	ayampi	even this
dutiyaṃ	api	dutiyampi	for the second time
evaṃ	api	evampi	even thus
kaṃ	asi	kaṃsi	who you are?
cakkaṃ	iva	cakkaṃva	like a wheel
rukkaṃ	iva	rukkhaṃva	like a tree

There are hundreds of examples with iva, with the meaning of a like or as. These are just from the Dhammapada:

cakkaṃva rukkhaṃva selaṃva seṭṭhaṃva abalassaṃva niratthaṃva khīraṃva nidhīnaṃva paṭivātaṃva ñātīnaṃva nakkhattapathaṃva bhantaṃva kaliṃva tulaṃva sāradikaṃva phalamicchaṃva abhivaṭṭhaṃva naḷaṃva bhadraṃva aggihuttaṃva candaṃva

Counter-examples:

ahaṃ + eva > ahameva

etaṃ + ahosi > etadahosi