An onomatopoeia most likely first used by The Notorious B.I.G. in his 1994 debut album (Ready to Die) song, Gimme The Loot. It's used to describe the sound of a gunshot and/or the sound(s) heard in a fight such as, Boom, Pow, Blam, etc.
2) Noun: A powerful punch, a knockout punch.
3) Noun: sound of a gunshot.
2)"I hit him with the blakka!- Blakkaman"
3)"dont worry bout your man thats why i carry the chopper it go blakka blakka, blakka ba blakka blakka'' - Ace hood