Words that only have vowels are called “vowel-only words” or “words with no consonants.” These types of words are relatively rare in English,
and they are usually monosyllabic (consisting of only one syllable).

1. Aeon: a period of time usually assumed to be about a thousand years

2. Aureate: having the golden color of an aureole

3. Eidolon: a phantom or ghost

4. Eucalypt: a tree or shrub belonging to the genus Eucalyptus

5. Ooze: a soft, wet, and slimy mass

6. Ouabain: a poisonous plant extract

7. Aeolian: relating to or caused by the wind

8. Eudiometer: an instrument used for measuring the volume of gases

9. Eugenic: relating to or promoting the improvement of the human race through
selective breeding

10. Eunuch: a man who has been castrated, typically for purposes of guarding
harems

11. Aioli: a sauce made from garlic and olive oil

12. Iou: a written promise to pay a specified amount to a person or organization

13. Oleander: a poisonous plant with showy flowers

14. Oleo: short for oleomargarine, a type of butter substitute

15. Ouija: a board with letters, numbers, and symbols used for communicating with
the dead

16. Ouphe: a mischievous sprite or elf