Antonyms of noun impossibility

1 of 2 senses of impossibility

Sense 1
impossibility, impossibleness -- (incapability of existing or occurring)
       Antonym of possibility (Sense 2)
      => possibility, possibleness -- (capability of existing or happening or being true; "there is a possibility that his sense of smell has been impaired")

Synonyms/Hypernyms (Ordered by Estimated Frequency) of noun impossibility

2 senses of impossibility

Sense 1
impossibility, impossibleness -- (incapability of existing or occurring)
       => nonexistence, nonentity -- (the state of not existing)

Sense 2
impossibility, impossible action -- (an alternative that is not available)
       => option, alternative, choice -- (one of a number of things from which only one can be chosen; "what option did I have?"; "there no other alternative"; "my only choice is to refuse")