Freebasing

[Becky]

The act of smoking a drug freebase. Freebase refers to the non-salt form of a drug. Drugs are usually converted to a water soluble salt so that they can be orally or intranasally consumed. The term freebase has nothing at all to do with the purity or potency of a drug.
For example, cocaine powder is cocaine hydrochloride, a water soluble salt. Being water soluble means that you can snort it, eat it, inject it, or plug it (put it up your ass) and you will get high. However, a cruder form of cocaine is cocaine freebase (i.e. crack), which is not water soluble and therefore cannot bet eaten or snorted. You must smoke it to feel the effects.
Its the same with methamphetamine. Meth freebase is an oily liquid, which your body cannot absorb, so the only way to get high from it is to smoke it. Crystal meth, however, has been converted to a water soluble salt, and can therefore be snorted, injected, etc.
The heat used to smoke freebase drugs generally destroys a large amount of the active drug you are trying to consume, therefore it is NOT an efficient route of administration. However, the high generally has a faster onset, and the physical act of smoking is generally pleasurable, so thats why we have people becoming addicted to crack. The duration from smoking crack is much shorter than the duration from snorting coke, but again, people like smoking things, so people enjoy crack. Youll actually get higher for longer if you snort cocaine hcl vs. smoking crack.

[Tina]

freebasing is typically referring to the act of smoking drugs, such as cocaine or heroin, most likely in a purified/concentrated form known as freebase (an example would be crack form of cocaine)
Apparently it produces an intense high quickly, but the effects typically do not last very long.