This episode uncovers the surprising histories of fragrant words. Many, including perfume, incense and bakhoor, trace back to roots connected with smoke and fumes. Eau de toilette may seem like an odd name for something sprayed on the body, but the history of the word toilet makes it clearer. Equally unexpected is potpourri, which goes back to a term meaning rotten pot. Find out why the number 5 became the name of the century's most iconic fragrance and the story behind the naming of the Marc Jacobs perfume line. We also look at the name origins of popular essential oils such as eucalyptus, lavender and tea tree, the latter with distinctly Australian roots.