Voiceless labiodental fricative

The voiceless labiodental fricative is a sound that occurs in some languages, represented as /f/ in the IPA.

Sound Changes

See also: Fricatives

To

A common origin of /f/ is the lenition of a voiceless bilabial stop such as *p or *pʰ. This can be part of a common stop lenition process, but may be independant, as in Arabic and Hungarian. The change commonly proceeds thru a bilabial intermediate [ɸ], so other outcomes are possible, eg. Celtic, where *sɸ → f, but *ɸ → h → ∅ otherwise. (See more at /p/, fricative.)

Many other fricatives can also change to /f/:

• θ → f (Oscan, Latin and most other Italic languages; some English dialects; some Oceanic branches)
• x → f (Oscan — but not Latin, where *x → h)
• xʷ → f (Oscan, Latin)
• ʍ → f (some English dialects)
• Devoicing: v → f. In many West Germanic varieties including Standard German, the change of *w → ʋ ~ v has pushed older †/v/ to /f/. This can be part of a more general devoicing process; see eg. final devoicing.

Other:

• w → f is found in Irish (when not intervocalic). Many different phonetic paths of development are possible here.
• sp → f in Albanian