CAN'T MAKE UP MY MIND

The following words share a very unusual quality. Can you determine what it is?

SANCTION

CLEAVE

BOUND

BOLT
MOOT
DUST
LEFT
CONSTRAINED

Answers:

They are all self-contradicting words - Auto-antonyms or Contronyms.

SANCTION means both to approve and condemn. CLEAVE means both to separate and adhere. BOUND means both to leap and tie down. BOLT means both to fasten securely and to run away. MOOT mean both worthy of consideration, as in debate, and unworthy of consideration or debate because the issue has been resolved or doesn't need to be resolved. DUST means both to remove dust and to sprinkle dust onto. LEFT means both gone and remaining. CONSTRAINED means both to feel forced to do something and also not to do something.