tetraoxide

Etymology tree
Proto-Indo-European *kʷetwóres
Proto-Hellenic *kʷétwores
Ancient Greek τέσσᾰρες (téssăres)
Ancient Greek τετρᾰ- (tetră-)bor.
English tetra-
Proto-Indo-European *h₂eḱ-der.?
Ancient Greek ὀξύς (oxús)
Proto-Indo-European *ǵenh₁-
Proto-Indo-European *-os
Proto-Indo-European *ǵénh₁os
Proto-Hellenic *génos
Ancient Greek γένος (génos)
French oxygène
Latin acidusbor.
French acide
blend
French oxidebor.
English oxide
English tetraoxide
From tetra- + oxide.