15. DREAMHOLEAnd those are just some of the more innocuous words from the list of 50 at mental_floss.
A dreamhole is a small slit or opening made in the wall of a building to let in sunlight or fresh air. It was also once used to refer to holes in watchtowers used by lookouts and guards, or to openings left in the walls of church towers to amplify the sounds of the bells.
According to one 19th century glossary of industrial slang, a fanny-blower or fanner was "used in the scissor-grinding industry," and comprised "a wheel with vanes, fixed onto a rotating shaft, enclosed in a case or chamber to create a blast of air." In other words, it’s a fan.
Fartlek is a form of athletic training in which intervals of intensive and much less strenuous exercise are alternated in one long continuous workout. It literally means "speed-play" in Swedish.