• beptunes,
• meptunes,
• jeptunes,
• heptunes,
• nwptunes,
• nsptunes,
• ndptunes,
• nrptunes,
• n4ptunes,
• n3ptunes,
• neotunes,
• neltunes,
• ne-tunes,
• nepptunes,
• neptunnes,
• naptunes,
• Nepturens,
• Nepturns,
• Naptures,
• Neaptunes

• neptunium,
• neptune.

The adjective form of the word "Neptunes" is "Neptunian".

The plural form of "neptunes" remains the same, as it is already a plural form referring to the multiple versions or aspects of the Roman god Neptune.

The singular form of the word "neptunes" is "neptune"