Atabrine \Atabrine\ n. [Trademark.] a drug once used to treat malaria ({C23H30ClN3O}); chemically it is a derivative of the tricyclic structure acridine: 6-chloro-9-[[4-(diethylamino-1-methylbutyl)]amino]-2-methoxyacridine. It also has some anthelmintic activity against cestodes. Atabrine is a trademark. Syn: quinacrine, mepacrine. [WordNet 1.5]