Still homonyms, if not homophones. Nevertheless, see: דבר=thing דבר=speech דבר=word Some spelled (or, spelt) the same, sound the same (homophones). Others, spelled the same, pronounced differently (homographs).
But we digress - why does פלאפל have an א? My guess is that it stems from an Aramaic word and is supposed to be pronounced with a distinctly א sound. Can anyone provide an answer?