Here are some good Jain boy names starting with the letter “D” (with simple meanings):

1. Darshan – Divine vision, right perception (samyag-darshan)
2. Devansh – Part of the divine
3. Dhruv – Fixed, steady, firm (symbol of steadfast faith)
4. Divyam / Divyank – Divine, full of purity
5. Dhanesh – Lord of wealth (can be taken in sense of spiritual wealth)
6. Deepak / Dipak – Lamp, one who gives light (of knowledge)
7. Dikshant – Related to initiation / religious vow (diksha)
8. Devendra – Lord of devas
9. Dharmik – Religious, righteous
10. Dayanand – One who rejoices in compassion (daya)

Specifically more traditional Jain‑flavoured names:

1. Dharmendra – Lord of dharma
2. Dharamveer / Dharmaveer – Brave in upholding dharma
3. Devkumar – Son of devas
4. Dharan – One who upholds (like one who holds vows)
5. Dishaant (Dishant) – One who shows / reaches the right direction

If you tell me whether you prefer very purely traditional Jain names or more modern sounding names, I can suggest a more focused list.