mountaineering a rule of thumb for calculating the time needed for a climbing expedition, allowing 1 hour for every 3 miles of distance plus 1 hour for every 2000 feet of height
Read more in this article about some frequently asked questions and fun facts related to our definitions.
Word Origin for Naismith's rule
C19: named after W. W. Naismith (1856–1935), Scottish climber, who formulated it
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012