[ati] generally means person or individual. As for the use of Rahi, I'm possibly thinking of not using it, since Rahi is really Matoran, and this is Okotan, fundamentally two different cultures, despite their similarities, purposeful or not.
[pa-ati] meaning person of autonomy
A bit later
I went through a couple ideas, but looking at some stems I think I'm going to go for [ ia ] or [ ita ] as a base for this word. As a base for the word animal, is where I need to begin. [umiu] is what I've gathered for unknown, and we can probably call the animals "unknown living beings", as I kinda doubt when the Okotan spoken language was canonically created, the Okotans would have known much about the wildlife.
ita came from a re-ordering of the word [ati] as [ati] means person, [ita] itself would put animacy or intentionality first, instead of thing or object. [ati] would then basically mean "Object(s) that have intention" and [ita] would mean the reverse "intentional object(s)". Sorry if it came from nearly nowhere.
Which led me to [ita-umiu] for animal, now for Beastly...
[pa] means possibility,potential; freedom, and autonomy. the suffix [-o] is used to create adjectives, so taking the previous [ita-umiu] and uisng phonological reduction, a process of slimming a word, to simplify it, happens all the time in natural languages, heck look at any word that originates from Latin as an example. Basically we can transform [ita-umiu] to [itami]
From [itami] meaning wildlife or animal I can get [itami-o] or [itamo] which would mean animal-like.
From this I finally arrive at [ati-itamo] which means "Beast-like person" and using my favorite friend phonological reduction, I can get [atami]. Which would basically mean Beast-Person.
Ati-itamo > Atitamo > Attamo > Atamo > Atami
Of course Your suggestions are really cool, so I tried to keep the end result similar to
since I think that was my major inspiration for the last sound change.
I may or may not geek out at stuff like this, I am sorry in advance.