>I think its sanskrit namah + te = namaste

The reason I prefer to write 'namas' is that the stem form really is
namas, with a final -s, like manas, apsaras. This is visible from the
forms namaskaroti and namasyati, and is the form in which the word
is cited in Apte, for example. There is a sandhi rule that 's' in
final position > visarga (.h) but I wouldn't apply it in the above
explication since it involves the detour: s > .h > s

best regards,

/Rett