ageratum

from WordNet (r) 3.0 (2006)

ageratum
    n 1: rhizomatous plant of central and southeastern United States
         and West Indies having large showy heads of clear blue
         flowers; sometimes placed in genus Eupatorium [syn:
         {mistflower}, {mist-flower}, {ageratum}, {Conoclinium
         coelestinum}, {Eupatorium coelestinum}]
    2: any plant of the genus Ageratum having opposite leaves and
       small heads of blue or white flowers

from The Collaborative International Dictionary of English v.0.48

Ageratum \A*ger"a*tum\ ([.a]*j[e^]r"[.a]*t[u^]m or
   [a^]j`[~e]r*[=a]"t[u^]m), prop. n. [NL., fr. Gr. 'agh`raton a
   sort of plant; 'a priv. + gh`ras old age.] (Bot.)
   A genus of plants, one species of which ({Ageratum
   Mexicanum}) has lavender-blue flowers in dense clusters.
   [1913 Webster]

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