Wiktionary
a. 1 not diplomatic or tactful 2 lacking sensitivity or the skill of dealing with others
WordNet
adj. not skilled in dealing with others [ant: diplomatic]
showing skill in handling difficult situations [syn: tactless]
Usage examples of "undiplomatic".
The Morganites, finding the entire business of tea worship incomprehensible, responded with further highly undiplomatic suggestions as to what the inhabitants of Portsmouth could do with their remaining tea.
He would henceforth deal only with Franklin, he announced, and in a pointedly undiplomatic conclusion, informed Adams, “Le Rot n'apas eu besoin de vos sollicitations pour s'occuper des interets des États-Unis.
He would henceforth deal only with Franklin, he announced, and in a pointedly undiplomatic conclusion, informed Adams, "Le Rot n'apas eu besoin de vos sollicitations pour s'occuper des interets des Etats-Unis.