ageratum Meaning, Definition & Usage

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

WordNet

A*ger"a*tum noun
Etymology
NL., fr. Gr. a sort of plant; priv. + old age.
Definitions
  1. (Bot.) A genus of plants, one species of which (A. Mexicanum) has lavender-blue flowers in dense clusters.

Webster 1913