say it: puh-TOO-nee-uh
petunia is a noun meaning "any of numerous tropical herbs having fluted funnel-shaped flowers". It carries 2 recorded senses.
any of numerous tropical herbs having fluted funnel-shaped flowers
annual or perennial herbs or shrubs of tropical South America
Forms marked · are formed by the regular rule rather than recorded in the source data. English keeps a few hundred irregulars and the rest follow the pattern, so the rule is right far more often than not — but it is a rule, and the mark says so.
Definitions, synonyms and semantic relations for petunia come from Princeton University’s WordNet. The pronunciation comes from the CMU Pronouncing Dictionary. Commonness is measured against a corpus of everyday English. Full sources and licences.