Tweak

TWEAK is a word often used to describe the illegal narcotic " crystal meth " also known as methamphetamine.

You: "Well why do we refer to meth as tweak anyway?"
Professor Pookie: Great question young smoker. I will tell you the origin and reason, listen carefully.

Long ago, many years ago crystal meth had just had become well known for being a white trash drug (commonly referred as "poor mans cocaine") and back then the drug was made with a key ingredient ephedrine which was later on banned in the U.S.A by the FDA in 2003. Long before it was banned, it was really purest dope you could get.
A man who apparently had never done the potent drug before in his life, decided to try it for the first time. In conclusion the man was wide awake, unable to sleep, eat, or sit down still. The meth was so strong at that time, that when you would talk you would speak way too fast.

Legend is that the man was asked how long he had been up for and in response the man answered in a very fast

tasmanian devil type of voice and said "TWOWEEKS, I BE UP TWOWEEKS NOW" and in conclusion it sounded like the man was saying "TWEAK" and from that point on it was associated with crystal meth.

"TWOWEEKS, I BE UP TWOWEEKS NOW" is the sentence that a man who had been high for two whole weeks said and made a compound "Tweak" be associated to the drug "crystal methamphetamine .