One “smoot” is five feet seven inches, or about 1.7 meters.

It’s named for Oliver R. Smoot, an ill-starred MIT pledge whose fraternity brothers rolled him head over heels to measure the length of the Harvard Bridge in October 1958.

The bridge measured “364.4 smoots plus one ear.” The markings are repainted each year by the incoming pledge class of Lambda Chi Alpha.

Ironically, Smoot later became chairman of the American National Standards Institute.