Sequoia, eulogia or miaoued are all good options, but there’s an even shorter (and more obscure) word with all the vowels and not a single consonant: Iouea. It’s not the kind of word you’d use at the dinner table, but it’s listed in the Wikipedia dictionary as a genus of Cretaceous fossil sponges.
If you got really tricky and tried to find a word that contained the letters in the phrase ‘all of the vowels’, you probably found, like I did, that there isn’t one. But it was still worth checking.
What is it that speaks without any words? And can be loudly and distinctly heard? Will drive away friend, and foe alike. And is enough to make a stolid man’s face alight?
A one way street sign. It tells you the correct way to go, is black and white (in the United States), going the wrong way can get you a citation and the sign only has two words on it.
You’re in a room with two doors. There’s a guard at each door. One door is the exit, but behind the other door is something that will kill you. You’re told that one guard always tells the truth and the other guard always lies. You don’t know which guard is which. You are allowed to ask one question to either of the guards to determine which door is the exit.
Ask either guard what door the other guard would say is the exit, then choose the opposite door.
If you ask the guard who always tells the truth, he knows the other guard would lie, so he’ll point you to the door leading to death. If you ask the guard who always lies, he knows the other guard would truthfully show you the exit, so he’ll lie and point you to the door leading to death.
An alternate solution is to ask a guard what they would answer if you were to ask them which door was the exit, then choose that door. The truthful guard will point to the correct exit, but the lying guard will too. Here’s why. If you asked him what door was the exit, he would normally lie and point to the death door, but you asked him what he would say if you asked what door was the exit, and in order to lie to that question, he will point you to the exit.