Green’s Dictionary of Slang

quiddish adj.

good-natured.

1747		Life and Character of Moll King 12: We had ne’er a Queer Cull, a Buttock, or a Porpus, amongst them, but all as Rum and as Quiddish as ever Jonathan sent to be great Merchants in Virginia. [Ibid.] 24: Rum or Quiddish, Good-natur’d.
1754		G. Stevens ‘A Cant Song’ Muses Delight 177: She said I must love you, you’re quiddish and bold.