Expletive infixation is a process by which an expletive or profanity is inserted into a word, usually for intensification. It is similar to tmesis, a word or phrase separated into two parts, e.g. ‘turn it off.’ The most commonly inserted English expletives are adjectival: either participles (fucking, mother-fucking, freaking, blooming, bleeding, damned) or adjectives (bloody). Although most speakers are not exposed to these formations until after childhood, they can form new examples readily once introduced to the process, and their judgments of which formations are acceptable are remarkably consistent. This suggests that the rules for the placement of the expletive are not arbitrary, but instead derive from fundamental aspects of English phonology.
A simple rule is that the insertion occurs at a syllable boundary, usually just before the primary stressed syllable. Thus, one hears abso-fuckin’-lutely rather than *ab-fuckin’-solutely. This rule is insufficient to describe examples such as un-fuckin’-believable, however, so modifications to this rule are proposed such as morpheme boundaries taking precedence over stress. Counterexamples to this exception do exist: unbe-fuckin’-lievable. A more fundamental theory due to John McCarthy is based on prosody, the rhythm, stress, and intonation of speech.
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