Step 1: Differentiate forms of cocaine. Cocaine is typically sold as a salt, cocaine hydrochloride, which is a powder that is snorted or dissolved and injected. This form does not vaporize well for smoking. To be smoked, it must be converted from its salt form to its "base" form.
Step 2: Identify the smokable form. The "base" form of cocaine, known as freebase or crack cocaine, has a lower melting point and can be effectively smoked. This is the pure alkaloidal form.
Step 3: Evaluate the slang terms.
- (1) Eve: A slang term for the drug MDEA.
- (2) Crystal: A common slang term for methamphetamine.
- (3) Base ball: A slang term for freebase or crack cocaine, sometimes referring to a mixture of the two. It directly relates to the term "base."
- (4) Angel dust: A slang term for the drug PCP.
Conclusion: "Base ball" is the slang term in the list that refers to the smokable, pure alkaloidal (base) form of cocaine.