hectometer (hm) : A metric unit of distance equal to 100 meters, 328.084 feet, or 109.361 yards. This unit isn't used much in everyday life in metric countries, but it appears in various scientific contexts.
Russ Rowlett (Director), How Many? A Dictionary of Units of Measurement, Center for Mathematics and Science Education University of North Carolina, USA 2005. http://www.unc.edu/~rowlett/units/dictA.html, (Unit of Meas and Covr Factors - Amer) {608}