A Roman unit of liquid volume. The word means "sixth", and the unit was equal to 1/6 congius. The sextarius held about 530 milliliters, roughly the capacity of the British and U.S. pints (568.261 and 473.176 milliliters, respectively)
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}