grandiloquent
adj. US //ɡɹænˈdɪɫəkwənt// UK //ɡɹˈændɪlˌɒkwənt// grandil·o·quent
From Middle French grandiloquent, from Latin grandiloquus, from grandis (“great, full”) + loquēns, present participle of loquor (“to speak”). Compare eloquent.