de·bate / diˈbāt/ • n. a formal discussion on a particular topic in a meeting or assembly, in which opposing arguments are put forward. ∎ an argument about a particular subject, esp. one in which many people are involved: the national debate on abortion.• v. [tr.] argue about (a subject), esp. in a formal manner. ∎ consider a possible course of action before reaching a decision: he debated whether he should leave.PHRASES: be open to debate be unproven; require further discussion.under debate being discussed or disputed.DERIVATIVES: de·bat·er n.