Antonyms of noun insignificance

1 sense of insignificance

Sense 1
insignificance -- (the quality of having little or no significance)
       Antonym of significance (Sense 1)
      => significance -- (the quality of being significant; "do not underestimate the significance of nuclear power")

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

1 sense of insignificance

Sense 1
insignificance -- (the quality of having little or no significance)
       => unimportance -- (the quality of not being important or worthy of note)