Expletive infixation is a process by which an expletive or profanity is inserted into a word, usually for intensification. Strictly speaking, it is an example of tmesis rather than infixation, since true infixes are bound morphemes.

The most commonly inserted expletives are adjectival: either participles (fucking, mother-fucking, blooming, bleeding, damned) or adjectives (bloody). They are usually somewhat phonetically reduced (fuckin).

The insertion occurs at a syllable boundary, usually just before the stressed syllable. Thus, one hears abso-fuckin-lutely rather than ab-fuckin-solutely. It can also occur at a morpheme boundary, for example un-fuckin-believable.

Examples

• fan-bloody-tastic
• guaran-damn-tee (Southwest American slang)
• "Ah, so loverly, sittin' abso-bloomin'-lutely still..." (from the song "Wouldn't It Be Loverly?" in the musical My Fair Lady)
• "the emanci-mother-fuckin-pator of the slaves" (from the musical Hair)
• "ri-goddamn-diculous" (attributed to John Wayne, in an address to some quondam graduating ROTC cadets)
• "abso-fraggin'-lutely" (catch phrase of character John Sheridan in the television show Babylon 5)
• "Ala-fucking-bama" (used in the movie My Cousin Vinny)