Physics:Acetabulum (unit)

In Ancient Roman measurement, the acetabulum was a measure of volume (fluid and dry) equivalent to the Greek ὀξύβαφον (oxybaphon). It was one-fourth of the hemina and therefore one-eighth of the sextarius. It contained the weight in water of fifteen Attic drachmae. Used with some frequency by Pliny the Elder, in a 1952 translation the unit was judged to be equivalent to 63 ml (2.2 imp fl oz; 2.1 US fl oz). However, other sources estimate a higher value of perhaps 68 ml (2.4 imp fl oz; 2.3 US fl oz) (see Ancient Roman units of measurement).

References

•  This article incorporates text from a publication now in the public domain: PS (1870). "Acetabulum". in Smith, William. Dictionary of Greek and Roman Antiquities. London: John Murray. https://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%3A1999.04.0063%3Aentry%3Dacetabulum-cn-02.