English words containing inserted expletives, like absobloodylutely or unbefuckinglievable, are often said to be created by ‘infixation’. One goal of this work is to argue that such claims are self-contradictory. Infixes are affixes, but the expletives are not. Rather, they are themselves morphologically complex, are not bound, and can occur with words from different syntactic categories. Hence, the expletives are full words, and the only property they share with infixes is their phonologically determined insertion point. Due to these factors, I suggest that words like absobloodylutely are discontinuous compounds instead, in which the expletive forms a new word with the word it interrupts. I further argue that discontinuous compounding is even rarer than actual infixation cross-linguistically, which makes English a typological outlier. On the other hand, I try to show that the apparently idiosyncratic properties of expletive compounds are compatible with English compounding at a more abstract level. In addition, the article seeks to establish some tentative diachronic and cognitive mechanisms that may have led to the emergence and retention of expletive insertion. The overall conclusion is that, once morphological phenomena are analyzed in sufficient detail, novel structural patterns and parallels may emerge.