{wa' nuvpu'vam} DIp-DIp tlhegh vIqeltaHvIS, mumISmoH vay'..

wa' (one) - singular
nuvpu' (people) - plural

But the {nuvpu'} is the head noun.. So, is the {wa' nuvpu'vam}
singular or plural ?

wa' is a number, not a noun. It does not participate in noun-noun constructions.

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SuStel
http://trimboli.name