The term "freebasing" is a misnomer as it refers to the composition of the drug. It does not mean "to smoke" the drug per se, but you cannot smoke morphine in its non-freebase form. Morphine freebase is just morphine. Most formulations of morphine are either morphine salts (MSO4) where the freebase is protonated, or morphine hydrochloride which is morphine that is treated with hydrochloric acid (HCl). In order to create morphine freebase, you have to extract the morphine from the formulation by chemically altering the composition. This is really no different to producing crack, which is the freebase of cocaine. The most common reason for producing morphine freebase is in order to make heroin, which can then be smoked or injected.

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To freebase morphine means to smoke that stuff off some foil with a straw.