Answer:
Which word is least like the others? Third, fourth, fifth, sixth, seventh, eighth, ninth?
What object has keys that open no locks, space but no room, and you can enter but not go in?
What can you easily break but never touch?
What can be broken without being touched?
It is a popular afterlife destination where you want to send people when you're mad at them.
As round as an apple. As deep as a cup. All the king's horses can't pull it up.