from
The Collaborative International Dictionary of English v.0.48
Kitcat \Kit"cat`\, a.
1. Designating a club in London, to which Addison and Steele
belonged; -- so called from Christopher Cat, a pastry
cook, who served the club with mutton pies.
[1913 Webster]
2. Designating a canvas used for portraits of a peculiar
size, viz., twenty-eight or twenty-nine inches by
thirty-six; -- so called because that size was adopted by
Sir Godfrey Kneller for the portraits he painted of the
members of the Kitcat Club. --Fairholt.
[1913 Webster]