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1962, American English, possibly from Yiddish glitsh "a slip," from glitshn "to slip," from German glitschen, and related gleiten "to glide" (see glide). Perhaps directly from German; it began as technical jargon in the argot of electronic hardware engineers, popularized and given a broader meaning by U.S. space program.
[fr German glitschen (or Yiddish glitshen), ''slip'']