This article focuses on French espèce de + NP! ‘you + NP!’ to make a case that impoliteness can be conventionalized in linguistic form beyond the level of the lexicon. We argue that the pattern can be considered a construction in its own right and also that it is strongly conventionalized for impoliteness in particular. To support this claim, we adopt both a corpus-based and a questionnaire-based approach. The corpus study reveals not only that espèce de + NP! mainly serves impolite purposes in actual usage but also that it tends to force an impolite interpretation onto noun phrases that do not themselves express negative evaluation. Our questionnaire study complements these findings by showing, inter alia, that the construction is generally judged to be ill-formed when combining with positively evaluative or evaluatively neutral nouns and, at the same time, that such nouns are indeed rated as impolite in the construction. It also points to a difference between calling someone espèce d’idiot! ‘you idiot!’ and calling them just idiot!. We conclude the article with some reflections on why espèce de + NP! is an impoliteness construction.