| Roman inch | |
| Standard: | Roman |
| Quantity: | length |
| Units1: | SI base units |
| Inunits1: | 24.6 mm |
| Units2: | U.S. customary |
| Inunits2: | 0.97 in |
The Latin: uncia (plural: Latin: unciae, lit. "a twelfth") was a Roman unit of length, weight, and volume. It survived as the Byzantine liquid ounce (Greek, Ancient (to 1453);: οὐγγία, oungía) and the origin of the English inch, ounce, and fluid ounce.
The Roman inch was equal to of a Roman foot (Latin: pes), which was standardized under Agrippa to about 0.97 inches or 24.6 millimeters.
The Roman ounce was of a Roman pound.[1]