tetrahydride

Etymology tree
Proto-Indo-European *kʷetwóres
Proto-Hellenic *kʷétwores
Ancient Greek τέσσᾰρες (téssăres)
Ancient Greek τετρᾰ- (tetră-)bor.
English tetra-
Proto-Indo-European *wed-
Proto-Indo-European *-r̥
Proto-Indo-European *wódr̥
Proto-Hellenic *údōr
Ancient Greek ῡ̆̔́δωρ (hū̆́dōr)
Ancient Greek ῠ̔δρο- (hŭdro-)der.
English hydro-
Proto-Indo-European *dʰeh₁-der.
Proto-Italic *-iðos
Latin -idusder.
English -ide
English hydride
English tetrahydride
From tetra- + hydride.