• siadophis,
• xiadophis,
• ciadophis,
• fiadophis,
• riadophis,
• eiadophis,
• duadophis,
• djadophis,
• dkadophis,
• doadophis,
• d9adophis,
• d8adophis,
• dizdophis,
• disdophis,
• diwdophis,
• diqdophis,
• diasophis,
• diaxophis,
• diacophis,
• diafophis

• diatomic,
• diaphragm,
• dialysis,
• diadem,
• diathesis,
• diagnosis,
• diaspora,
• diapause,
• Diabolo,
• dialect,
• Diabase,
• diabetes,
• diagonal,
• diagnose,
• dyad.

The adjective form of the word "diadophis" is "diadophid".

The plural form of the word "diadophis" is "diadophises".

The singular form of the word "diadophis" is "diadophis". This word does not change between plural and singular forms. It is the scientific name of a genus of snakes and is used as such in both cases.