c.1200, from O.Fr. conestable, principal officer of the Frankish king's household, from L.L. comes stabuli, lit. "count of the stable" (established by Theodosian Code, c.438 C.E.), hence, "chief groom." Probably a translation of a Gmc. word. Meaning "an officer of the peace" is from c.1600, transferred to "police officer" 1836.