To get so drunk and shitfaced that you don't give a fuck or a shit about what is going on. The point past being lit. A mixture of booze, duck farts, weed, cocaine, and meth will get you feeling schwarked
A co-worker is notorious for staying long past scheduled shift time, which often results in later scheduled employeesleaving before he does. It is referred to as "being Schaared."
When you are overly high or drunk. This can be from several things ranging from nicotine to weed to lean to alcohol. To know if you are schmacked look yourself in a mirror and see if you can stand still. If this objective is failed then your SCHMACKED.