Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
grandĭlŏquus, i, m. [grandis-loquor], speaking grandly or loftily: et grandiloqui, ut ita dicam, fuerunt cum ampla et sententiarum gravitate et majestate verborum, Cic. Or. 5, 20; cf. Quint. 10, 1, 66: stilus, Serv. Verg. Vit.
In a bad sense, grandiloquent: isti grandiloqui (i. e. Stoici), boasters, Cic. Tusc. 5, 31, 89.