In addition to thin concepts like the good, the bad and the ugly, our evaluative thought and talk appeals to thick concepts like the lewd and the rude, the selfish and the cruel, the courageous and the kind -- concepts that somehow combine evaluation and non-evaluative description. Thick concepts are almost universally assumed to be inherently evaluative in content, and many philosophers claimed them to have deep and distinctive significance in ethics and metaethics. In this first book-length treatment of thick concepts, Pekka Vayrynen argues that all this is mistaken. Through detailed attention to the language of thick concepts, he defends a novel theory on which the relationship between thick words and evaluation is best explained by general conversational and pragmatic norms. Drawing on general principles in philosophy of language, he argues that many prominent features of thick words and concepts can be explained by general factors that have nothing in particular to do with being evaluative. If evaluation is not essential to the sort of thinking we do with thick concepts, claims for the deep and distinctive significance of the thick are undermined. TheLewd, the Rude and the Nasty is a fresh and innovative treatment of an important topic in moral philosophy and sets a new agenda for future work. It will be essential reading to anyone interested in the analysis and the broader philosophical significance of evaluative and normative language.