prodigious(very big in size or quantity, see also: gigantic; huge) adjective [UK: prə.ˈdɪ.dʒəs] [US: prə.ˈdɪ.dʒəs]
tremendous(extremely large (in amount, extent, degree etc.) or great; enormous; extraordinary) adjective [UK: trɪ.ˈmen.dəs] [US: trə.ˈmen.dəs]John has a tremendous vocabulary. = John har ett enormt ordförråd.
vast [vaster, vastest](very large or wide (literally or figuratively)) adjective [UK: vɑːst] [US: ˈvæst]