"ageratums" in the noun sense
1. mistflower, mist-flower, ageratum, Conoclinium coelestinum, Eupatorium coelestinum
rhizomatous plant of central and southeastern United States and West Indies having large showy heads of clear blue flowers sometimes placed in genus Eupatorium
2. ageratum
any plant of the genus Ageratum having opposite leaves and small heads of blue or white flowers
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