TobyBartels on Nostr: : It's because the sound was originally [ɸ] (the unvoiced bilabial fricative), which ...

: It's because the sound was originally [ɸ] (the unvoiced bilabial fricative), which isn't used in English but lies between [f] (the unvoiced labiodental fricative, the usual sound of the phoneme /⁠f/ with the typical spelling ⟨f⟩) and [ʍ] (the unvoiced labiovelar fricative, the usual sound of the phoneme /⁠ʍ/ in conservative speech with the typical spelling ⟨wh⟩), which are. But [ʍ] is now largely obsolete, increasingly replaced with [w] (the voiced labiovelar approximant, the sound of the phoneme /⁠w/ with the typical spelling ⟨w⟩). So the first English speakers to transliterate Maori heard /⁠ɸ/ as /⁠ʍ/ rather than /⁠f/ and so wrote it as ⟨wh⟩, even though English speakers today almost always hear it as /⁠f/. And to make the choice even stranger, many Maori speakers today say [f], thanks to the influence of English. So the spelling only makes any sense if you compare conservative Maori pronunciation and conservative English pronunciation.