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Webster 1913 Edition

Noun.

The quality of being arch; cleverness; sly humor free from malice; waggishness.

Goldsmith.

Noun.

Cunning; shrewdness; waggishness.

archness ‎(countable and uncountable, plural archnesses)

The state of being arch.
- 1811, Jane Austen, Sense and Sensibility, chapter 18
  Marianne was surprised and confused, yet she could not help smiling at the quiet archness of his manner
- 2004, Alan Hollinghurst, The Line of Beauty, Bloomsbury, 2005, Chapter 3,
  There was something artless in Toby's delivery; he was working in the family tradition of teasing, but he was too relenting and couldn't yet match Gerald's heavy archness.