1. Solid
2. Essential
3. Material
4. Meaningful
5. Significant
6. Tangible
7. Valuable
8. Critical
9. Relevant
10. Notable
11. Considerable
12. Durable
13. Forceful
14. Potent
15. Pervasive
16. Concrete
17. Appreciable
18. Considerable
19. Profound
20. Lasting
21. Thorough
22. Resolute
23. Robust
24. Weighty
25. Worthy
26. Valid
27. Vigorous
28. Solidified
29. Definitive
30. Pronounced

When searching for synonyms for the word “substantive”, there are plenty of best ideas and other words that can be used. Many people opt for words like “solid”, “essential”, “material”, “meaningful”, and “significant”, but there are plenty of other words that could be used. Other words for “substantive” include “tangible”, “valuable”, “critical”, “relevant”, “notable”, “considerable”, “durable”, “forceful”, “potent”, and “pervasive”. There are also words like “concrete”, “appreciable”, “profound”, “lasting”, “thorough”, “resolute”, “robust”, “weighty”, “worthy”, “valid”, “vigorous”, “solidified”, “definitive”, and “pronounced” that can be used to describe the same concept. With so many synonyms available, it’s easy to find the perfect word to fit any situation.