What does Brandt mean? Brandt [brandt] as a name for boys is an Old English name, and the name Brandt means sword; fiery torch, beacon. Brandt is a German form of Brand (Old Norse, Old English). Brandt is also a variant of Brant (Old English). Associated with: old english, sword (warrior), fiery. Brandt has 2 variants: Brannt and Brantt.