• fitzroria,
• fitzorya,
• fitzroia,
• fitzroyaa,
• fritzroya,
• fitzrryoa,
• fitrzoya,
• fitzrooya,
• firztoya

• fiction,
• feature,
• fossil,
• fortuitous,
• fetish,
• fictitious,
• frenzy,
• fruitful,
• fetus,
• fixture,
• frizzy.

The adjective form of the word "fitzroya" is "fitzroyan".

The plural form of "fitzroya" is "fitzroyas".

The singular form of the word "fitzroya" is "fitzroya". The word itself is not plural or singular, as it is a proper noun referring to a specific genus of tree native to South America.