An eight letter word with three vowels using those letters is scavenge.
Eight letter words with four vowels using those letters are agencies and envisage.
Xylophone
elephant
monsoons
queueing
Maybe eight letters- there is rhythms which has NO vowels and is seven lettersso changing it slightly to rhythmic makes eight letters.
queueing
The Greeks added eight extra letters and modified the symbols for the letters.
Dopamine. I'm sure that there are others but I can't think of them at the moment.
Eight letter word using the letters, naloeyianrgt: yearning. gyration. learning.
There are no eight letter words using these letters.The longest possible words have seven letters and include:CatfallChapletFlatcapHellcatHematalPalmatePatellaPlacate
Eight letter words: hostelry, overshot
I think the largest eight letter number is 'trillion' but 'thousand' also has eight letters.