1. Link
2. Bond
3. Connection
4. Alliance
5. Union
6. Affiliation
7. Linkage
8. Interaction
9. Liaison
10. Rapport
11. Ties
12. Intercourse
13. Alliance
14. Rapport
15. Attachment
16. Accord
17. Involvement
18. Interconnection
19. Interdependence
20. Association
21. Cooperation
22. Affinity
23. Understanding
24. Intimacy
25. Sympathy
26. Friendship
27. Communion
28. Interplay
29. Involvement
30. Compatibility

When looking for other words for relationships, there are many options to choose from. Whether you are looking for a formal term or a more casual one, there is a wide variety of synonyms that can be used. For formal relationships, words like connection, affiliation, alliance, and liaison are some of the best options. For more casual relationships, words like ties, attachment, and friendship are great ideas. No matter what type of relationship you are trying to describe, there is likely a perfect synonym to fit the situation. With the list above, you can find the best word to express the relationship between two people or entities.