Boswellox
Boswellox, or Boswollocks as Karl pronounced it, is the name of an ingredient found in a range of anti-wrinkle creams which served as an example of how we are, in the opinion of Karl, running out of words.
Mentioned in the Ricky Gervais Guide to the Future, Karl claims that Boswellox was a terrible name for an ingredient, unlike Sodium which he liked. He then challenged Ricky and Steve to come up with a new word which could serve as the name for an ingredient in order to prove his point before accepting Ricky's second attempt; the word "Skrimpton".