Noun
slan (plural slans)
(dated, fandom slang) A fan of science fiction.
Fans are slans A.E. van Vogt 's 1940 novel Slan was about a mutant variety of humans who are superior to regular humanity and are therefore hunted down and killed by the normal human population. Source: Internet
Van Vogt's first completed novel, and one of his most famous, is Slan (Arkham House, 1946), which Campbell serialized in Astounding September to December 1940. Source: Internet