Synonyms of the word 
IMPOSSIBLENESS → IMPOSSIBILITY - NONENTITY - NONEXISTENCE
impossibleness
- n. Quality of being impossible.
impossibility
- n. Something that is impossible.
- n. (uncountable) The quality of being impossible.
- n. (obsolete) Inability; helplessness.
nonentity
- n. an unimportant or insignificant person.
- n. (uncountable): the state of not existing; nonexistence.
nonexistence
- n. The state of not existing.
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