• vrachychiton populneus,
• nrachychiton populneus,
• hrachychiton populneus,
• grachychiton populneus,
• beachychiton populneus,
• bdachychiton populneus,
• bfachychiton populneus,
• btachychiton populneus,
• b5achychiton populneus,
• b4achychiton populneus,
• brzchychiton populneus,
• brschychiton populneus,
• brwchychiton populneus,
• brqchychiton populneus,
• braxhychiton populneus,
• bravhychiton populneus,
• brafhychiton populneus,
• bradhychiton populneus,
• bracgychiton populneus,
• bracbychiton populneus

The adjective form of "Brachychiton Populneus" is "brachychitonic".

The plural form of the word "Brachychiton Populneus" would simply be "Brachychiton Populneus" as it is the scientific name of a specific species of tree. The plural form of scientific names does not typically change.

The singular form of the word "Brachychiton Populneus" is "Brachychiton Populneus". This is the scientific name of a species of tree commonly known as the "bottletree" or "kurrajong". The scientific name remains the same in both singular and plural forms.