From The Collaborative International Dictionary of English v.0.48 :
Canna \Can"na\, n. [L., a reed. See Cane.] (Bot.)
A genus of tropical plants, with large leaves and often with
showy flowers. The Indian shot ({Canna Indica) is found in
gardens of the northern United States.
[1913 Webster]
From The Collaborative International Dictionary of English v.0.48 :
Canna \Can"na\, n. [It.]
A measure of length in Italy, varying from six to seven feet.
See Cane, 4.
[1913 Webster]
From WordNet (r) 3.0 (2006) :
canna
n 1: any plant of the genus Canna having large sheathing leaves
and clusters of large showy flowers