With the aid of the American Heritage Dictionary of the English Language, which contains 46 pages of Indo-Eurpoean roots, one can discover that words that appear to be completely unrelated are in reality cognates. This information can be used to develop riddles that contain two or more such words. The point of an etymology riddle is that the cognate words share a common semantic element that is not readily apparent because some of the semantic and/or phonological changes that have occurred over the centuries have masked the common origin of the cognates.
Lazerson, Barbara Hunt
Word Ways: Vol. 12
, Article 11.
Available at: http://digitalcommons.butler.edu/wordways/vol12/iss2/11