"Reefer" is one of the oldest terms for marijuana, dating back to the early 1900s. Its origin is often attributed to Mexican Spanish, where "grifa" was slang for marijuana, and eventually, the term morphed into "reefer" in American slang. The word gained notoriety with the 1936 propaganda film Reefer Madness, which warned of the supposed dangers of marijuana use. Though considered somewhat outdated today, "reefer" is still used nostalgically by older generations or in pop culture to refer to cannabis.