[ 'tɛtrα:k ]
■ noun (in the Roman Empire) the governor of one of four divisions of a country or province.
↘one of four joint rulers.
↘ archaic a subordinate ruler.
Derivatives
~y noun ( plural ~ies ).
Origin
OE, from late L. ~a , from L. ~es , from Gk tetrarkhēs , from tetra- 'four' + arkhein 'to rule'.