təˈni.trəwəs adjective
also to·nit·ru·ant -wənt
Etymology: tonitruous from Latin tonitruum thunder (from tonitrus thunder, from tonare to thunder) + English -ous; tonitruant from Late Latin tonitruant- tonitruans, from present participle of tonitruare to thunder, from Latin tonitruum thunder — more at thunder
: thundering , fulminating