Origin of uncial
- From Late Latin ūnciālēs (litterae) inch-high (letters), uncials pl. of Latin ūnciālis inch-high from ūncia a twelfth part, ounce, inch oi-no- in Indo-European roots
From American Heritage Dictionary of the English Language, 5th Edition
- Attested 1712, from Late Latin unciales (“uncials"), unciales litterae (“uncial letters") (Jerome), plural of uncialis (“pertaining to one twelfth part, ounce, or inch"), from uncia (“one twelfth part, ounce, inch"). The literal meaning is unclear: some references indicate "inch-high letters", but see “Uncial script" in Wikipedia.