Definition of boom boom in English:

boom boom

phrase

British
informal
  • An exclamation made after delivering the punchline of a joke.

    • ‘As Basil Brush used to say, ‘boom boom’!’
    • ‘Unfortunately, I have a conscience (although the band seem to have taken a day off for theirs - boom boom!).’
    • ‘I've answered this question in some election hustings by saying I'd be the fish that swims against the tide… boom boom.’