Why is Filipino spelt with an F while the Philipines are spelt with a PH?
The Philippines and relative Philippine is English (under direct US influence since 1898 until end of WWII); Filipino is Spanish (under Spanish influence since Spanish emperor Philip II, XVI century, until 1898); Pilipino is the Tagalog transliteration of the Spanish adjective above (current local term). General note: English ph (to be pronounced f) always comes from ancient Greek words borrowed by Latins at Cicero’s times – actually, Latins realized that the sound was like an aspirated Latin p (neither simple p nor Latin f). That’s why they transliterated it into p + h. Later, that sound moved to an actual f, but the writing remained ph in French, English, etc., but reduced to simple f in Spanish, Italian, etc. On the other hand, native Tagalog speakers don’t have any f sound – p comes back!