veg-o
Some four letter words that end with "o" are:zerohaloherohobointojudokiloalsoaltoautoechomemoontopolosilosolotacotarotrioundoveto
fort
Yoyo.
Potato or tomato
There are not many 4 letter words that end with an O. However, there is trio, as well as taco.
Are you sure it ends in 'o'? A muon is a four letter subatomic particle.
veto
Onion.
Edamane is a vegetable. It is a bean.
okra
it'ev
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