Classification
Kingdom: Plantae (2635)
Phylum: Tracheophyta (2573)
Class: Magnoliopsida (2146)
Order: Asterales (237)
Family: Asteraceae (221)(family description)
Genus: Ageratina (2)
Epithet: ligustrina (DC.) R.M.King & H.Rob. (2)
Synonyms: Ageratina caecilia (B.L.Rob.) R.M.King & H.Rob., Ageratina plethadenia (Standl. & Steyerm.) R.M.King & H.Rob., Ageratum glaucum hort. ex Sieber & Voss, Eupatorium biceps Klotzsch ex Vatke, Eupatorium caeciliae B.L.Rob., Eupatorium erythropappum B.L.Rob., Eupatorium glabellum hort. ex Sieber & Voss, Eupatorium ligustaefolium DC., Eupatorium ligustrinum DC., Eupatorium micranthum Less., Eupatorium myriadenium Schauer, Eupatorium odoratissimum hort. ex Sieber & Voss, Eupatorium plethadenium Standl. & Steyerm., Eupatorium popocatapetlense Schlechtend., Eupatorium semialatum Benth., Eupatorium vetularum Standl. & Steyerm., Eupatorium weinmannianum Regel & Körn.
biceps => double-headed
caeciliae => in honor of Cecil Joslin Brooks (1875–1953), English plant collector in Borneo and Sumatra
glaucum => greyish or bluish
ligustrina => resembles Ligustrum
ligustrinum => resembles Ligustrum
micranthum => small flowered
odoratissimum => of very sweet odour
semialatum => half winged, more or less winged, occasionally winged
vetularum => of old women
weinmannianum => in honor of Johann Wilhelm Weinmann (1683-1741), apothecary and botanist [?]