• materfully,
• masterfuly,
• masterfull,
• masterfly,
• nasterfully,
• kasterfully,
• jasterfully,
• mzsterfully,
• mssterfully,
• mwsterfully,
• mqsterfully,
• maaterfully,
• masterfilly,
• maserfully,
• mastefully,
• mastfully,
• mastefullly,
• mastorfully,
• maisterfully,
• mosterfully

• masterful,
• masterly,
• Masseter,
• master copy,
• mastered,
• master class,
• master file,
• masterless,
• master plan,
• mastering,
• Masterson,
• master key,
• Masterman.

The adjective form of the word "masterfully" is "masterful".

The plural form of "masterfully" is "masterfully". The word does not have a distinct plural form, as it is an adverb and does not require pluralization.

The singular form of the word "masterfully" is "masterful"