Meaning of smack talk in English:

smack talk

noun

mass noun informal US
  • Boastful or insulting speech, especially as intended to demoralize or humiliate an opponent.

    • ‘a game like this promotes smack talk’

verb

(also smack-talk)
[no object] informal US
  • Make boastful or insulting remarks, especially in order to demoralize or humiliate an opponent.

    • ‘I don't smack-talk — I'd rather just be playing hard and putting my focus on the game’