late 14c., "to quarrel, dispute," also "to combat, fight, make war" (senses now archaic), also "discuss, deliberate upon the pros and cons of," from Old French debatre (13c., Modern French débattre), originally "to fight," from de- "down, completely" (see de-) + batre "to beat," from Latin battuere "beat" (see batter (v.)).
And he began for to debate; He smote þe porter. ["Robert of Sicily," c. 1500]
Transitive sense of "to contend about in argument" is from mid-15c.; that of "argue for or against in public" is from 1520s. Related: Debated; debating.
early 14c., "a quarrel, dispute, disagreement" (now archaic), from Old French debat, from debatre(see debate (v.)). Sense of "contention by argument" is from late 14c., that of "a formal dispute, a debating contest, interchange of arguments in a somewhat formal manner" is perhaps from early 15c.