Ancient Abbreviation It is not known as to exactly how length in cubits was abbreviated but iit can be inferred that abbreviations were used in those days. However, a cubit, s…pelled "×××" is such a short word in ancient Hebrew that it didn't need to be abbreviated Units of measurement may have been purposely given short names so writing their name would be quick. People of antiquity would probably have simply written cubit as: ××× .
Citations: and .
Modern Abbreviation There is no official modern English abbreviation for a cubit. The letters "cu" stand for copper and may cause ambiguity, as does "cb" for cubic and "ct" for computed topograph (used for measuring X-ray attenuation) so one should stay away from those abbreviations. In the rare case of the use of the cubit it is typically abbreviated: cbt. .