bamf /bamf/ 1. [from X-Men comics; originally "bampf"] interj. Notional sound made by a person or object teleporting in or out of the hearer's vicinity. Often used in {virtual reality} (esp. {MUD}) electronic {fora} when a character wishes to make a dramatic entrance or exit. 2. The sound of magical transformation, used in virtual reality {fora} like sense 1.