TWACK v. To strike with great force using the back of the middle finger (usually the nail) after coiling it under pressure against the opposing thumb. Accomplished twackers can inflict great welts upon their victim's flesh.
Synonyms for twack
On this page, you will find 30 slang terms related to twack. Some of the top words include: slap, tolcheck, bird, the bird, melee, and 25 more.