Полк. Дянко Марков [CC BY-SA (https://creativecommons.org/licenses/by-sa/3.0)]
- Origin: Bulgarian Тервел
- Meaning: unknown
- Gender: masculine
- (TAIR-vel)
The name is of unknown etymology. It was borne by an 8th-century Bulgarian khan of the Dulo Clan who was given the title of Caesar by Justinian II, the first known foreign ruler to receive such a distinction in Byzantine history.
Other forms include Tarvel, Terval, and the Greek Terbelis.
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