From The Collaborative International Dictionary of English v.0.48 [gcide]:
Petunia \Pe*tu"ni*a\ (p[-e]*t[=u]"n[i^]*[.a]), n. [NL., fr.
Braz. petun tobacco.] (Bot.)
A genus of solanaceous herbs with funnel-form or
salver-shaped corollas. Two species are common in
cultivation, Petunia violacea, with reddish purple flowers,
and Petunia nyctaginiflora, with white flowers. There are
also many hybrid forms with variegated corollas.
[1913 Webster] Petuntse
Petunse