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 ]