different between insignificance vs insignificancy

English

From in- +? significance.

insignificance (countable and uncountable, plural insignificances)

insignificant +? -cy or insignificance +? -y

insignificancy (countable and uncountable, plural insignificancies)

(obsolete) Lack of signification; meaninglessness.
Unimportance, insignificance.
- 1792, Mary Wollstonecraft, A Vindication of the Rights of Woman, Penguin 2004, p. 67:
  The argument may fairly be extended to women; for, seldom occupied by serious business, the pursuit of pleasure gives that insignificancy to their character which renders the society of the great so insipid.
An insignificant person or thing.

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