Voiceless labiodental affricate

A voiceless labiodental affricate ([p̪͜f] in IPA) is a rare affricate consonant that is initiated as a labiodental stop [p̪] and released as a voiceless labiodental fricative [f].

The XiNkuna dialect of Tsonga has this affricate, as in [tiɱp̪͡fuβu] "hippopotamuses" and aspirated [ɱp̪͡fʰuka] "distance" (compare [ɱfutsu] "tortoise", which shows that the stop is not epenthetic), as well as a voiced labiodental affricate, [b̪͡v], as in [ʃileb̪͡vu] "chin". There is no voiceless labiodental fricative [f] in this dialect of Tsonga, only a voiceless bilabial fricative, as in [ɸu] "finished". (Among voiced fricatives, both [β] and [v] occur, however.)

German has a similar sound /p͡f/ in Pfeffer /ˈp͡fɛfɐ/ ('pepper') and Apfel /ˈap͡fəl/ ('apple'). Phonotactically, this sound does not occur after long vowels, diphthongs or /l/. It differs from a true labiodental affricate in that it starts out bilabial, but then the lower lip retracts slightly for the frication.

In many varieties of Central Plains Mandarin and Lanyin Mandarin, labialized retroflex fricatives and affricates [ʂʷ][tʂʷ][tʂʰʷ] (sometimes including [ʐʷ~ɻʷ]) become labiodental, respectively resulting in the production of [f][p̪͡f][p̪͡fʰ] (sometimes including [v]).

The sound occurs occasionally in English, in words where one syllable ends with "p" and the next starts with "f", like in "helpful" or "stepfather".