Definition of "Foo"

Foo

proper noun
1. (dated, fandom slang, humorous) A mock deity of early science fiction fandom; a fannish ghod.
  Quotations
  Robert Bloch has blown his top. Backwards or forwards (or sideways) Foo ((ugh)) and Ghu ((!)) cannot be united! Does one eat chocolate cake with catsup on it? If you do and enjoy it then go off and be a fooghuist in your own little corner. You may as well worship Roscoe. Or Alpaugh. Foo fans are happy fans. Ghu isn't really helping Hoffman put out a fine mag you know. The fans who read Q are probably -- for the most part -- Foofooists.
  1951 November, Pike Pickens, “Sez You”, in Quandry‎, number 15, archived from the original on 7 June 2011
  I imagine it must be pretty discouraging to send out a whole issue of a fanzine and get nothing back but a couple of poctsarcds.[sic] I wouldn't know, thank Foo.
  1955 January, Dean Grennell, “Filler #523”, in Abstract‎, number 9
  You’ll never guess what Wollheim’s men have found!¶ A forest full of perfect echo-ﬂowers.¶ Honest to Foo! He says ”Salad!” to them,¶ And they obediently answer back, “Salad!”
  2004 September, Jack Speer, “Last and First Fen”, in Noreascon 4 Souvenir Book‎, page 57